feat: remove workaround for old filtermail

Filtermail fix <https://github.com/chatmail/relay/pull/497> was merged more than a year ago.
2026-05-14 04:16:30 +03:00 · 2026-05-12 23:31:00 +02:00
48 changed files with 501 additions and 672 deletions
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2608,25 +2608,6 @@ dependencies = [
 "libm",
 ]

-[[package]]
-name = "hybrid-array"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f2d35805454dc9f8662a98d6d61886ffe26bd465f5960e0e55345c70d5c0d2a9"
-dependencies = [
- "typenum",
-]
-
-[[package]]
-name = "hybrid-array"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "891d15931895091dea5c47afa5b3c9a01ba634b311919fd4d41388fa0e3d76af"
-dependencies = [
- "typenum",
- "zeroize",
-]
-
 [[package]]
 name = "hyper"
 version = "1.9.0"
@@ -3276,16 +3257,6 @@ dependencies = [
 "cpufeatures 0.2.17",
 ]

-[[package]]
-name = "kem"
-version = "0.3.0-pre.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b8645470337db67b01a7f966decf7d0bafedbae74147d33e641c67a91df239f"
-dependencies = [
- "rand_core 0.6.4",
- "zeroize",
-]
-
 [[package]]
 name = "lazy_static"
 version = "1.5.0"
@@ -3499,35 +3470,6 @@ dependencies = [
 "windows-sys 0.61.1",
 ]

-[[package]]
-name = "ml-dsa"
-version = "0.0.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ac4a46643af2001eafebcc37031fc459eb72d45057aac5d7a15b00046a2ad6db"
-dependencies = [
- "const-oid",
- "hybrid-array 0.3.1",
- "num-traits",
- "pkcs8",
- "rand_core 0.6.4",
- "sha3",
- "signature",
- "zeroize",
-]
-
-[[package]]
-name = "ml-kem"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8de49b3df74c35498c0232031bb7e85f9389f913e2796169c8ab47a53993a18f"
-dependencies = [
- "hybrid-array 0.2.3",
- "kem",
- "rand_core 0.6.4",
- "sha3",
- "zeroize",
-]
-
 [[package]]
 name = "moka"
 version = "0.12.10"
@@ -4263,8 +4205,6 @@ dependencies = [
 "k256",
 "log",
 "md-5",
- "ml-dsa",
- "ml-kem",
 "nom 8.0.0",
 "num-bigint-dig",
 "num-traits",
@@ -4283,7 +4223,6 @@ dependencies = [
 "sha2",
 "sha3",
 "signature",
- "slh-dsa",
 "smallvec",
 "snafu",
 "twofish",
@@ -5748,25 +5687,6 @@ dependencies = [
 "autocfg",
 ]

-[[package]]
-name = "slh-dsa"
-version = "0.0.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bd2f20f4049197e03db1104a6452f4d9e96665d79f880198dce4a7026ba5f267"
-dependencies = [
- "const-oid",
- "digest",
- "hmac",
- "hybrid-array 0.3.1",
- "pkcs8",
- "rand_core 0.6.4",
- "sha2",
- "sha3",
- "signature",
- "typenum",
- "zerocopy",
-]
-
 [[package]]
 name = "smallvec"
 version = "1.15.1"
@@ -7505,9 +7425,9 @@ checksum = "2164e798d9e3d84ee2c91139ace54638059a3b23e361f5c11781c2c6459bde0f"

 [[package]]
 name = "zerocopy"
-version = "0.7.35"
+version = "0.7.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1b9b4fd18abc82b8136838da5d50bae7bdea537c574d8dc1a34ed098d6c166f0"
+checksum = "74d4d3961e53fa4c9a25a8637fc2bfaf2595b3d3ae34875568a5cf64787716be"
 dependencies = [
 "byteorder",
 "zerocopy-derive",
@@ -7515,9 +7435,9 @@ dependencies = [

 [[package]]
 name = "zerocopy-derive"
-version = "0.7.35"
+version = "0.7.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
+checksum = "9ce1b18ccd8e73a9321186f97e46f9f04b778851177567b1975109d26a08d2a6"
 dependencies = [
 "proc-macro2",
 "quote",
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -78,7 +78,7 @@ num-derive = "0.4"
 num-traits = { workspace = true }
 parking_lot = "0.12.4"
 percent-encoding = "2.3"
-pgp = { version = "0.19.0", features = ["draft-pqc"], default-features = false }
+pgp = { version = "0.19.0", default-features = false }
 pin-project = "1"
 qrcodegen = "1.7.0"
 quick-xml = { version = "0.39", features = ["escape-html"] }
--- a/deltachat-ffi/deltachat.h
+++ b/deltachat-ffi/deltachat.h
@@ -413,6 +413,11 @@ char*           dc_get_blobdir               (const dc_context_t* context);
 *                    Messages in the "saved messages" chat (see dc_chat_is_self_talk()) are skipped.
 *                    Messages are deleted whether they were seen or not, the UI should clearly point that out.
 *                    See also dc_estimate_deletion_cnt().
+ * - `delete_server_after` = 0=do not delete messages from server automatically (default),
+ *                    1=delete messages directly after receiving from server, mvbox is skipped.
+ *                    >1=seconds, after which messages are deleted automatically from the server, mvbox is used as defined.
+ *                    "Saved messages" are deleted from the server as well as emails, the UI should clearly point that out.
+ *                    See also dc_estimate_deletion_cnt().
 * - `media_quality` = DC_MEDIA_QUALITY_BALANCED (0) =
 *                    good outgoing images/videos/voice quality at reasonable sizes (default)
 *                    DC_MEDIA_QUALITY_WORSE (1)
@@ -1456,16 +1461,16 @@ dc_chatlist_t*     dc_get_similar_chatlist   (dc_context_t* context, uint32_t ch

 /**
 * Estimate the number of messages that will be deleted
- * by the dc_set_config()-option `delete_device_after`.
+ * by the dc_set_config()-options `delete_device_after` or `delete_server_after`.
 * This is typically used to show the estimated impact to the user
 * before actually enabling deletion of old messages.
 *
 * @memberof dc_context_t
 * @param context The context object as returned from dc_context_new().
- * @param from_server Deprecated, pass 0 here
+ * @param from_server 1=Estimate deletion count for server, 0=Estimate deletion count for device
 * @param seconds Count messages older than the given number of seconds.
 * @return Number of messages that are older than the given number of seconds.
- *     Messages in the "Saved Messages" chat are not counted as they will not be deleted automatically.
+ *     Messages in the "saved messages" folder are not counted as they will not be deleted automatically.
 */
 int             dc_estimate_deletion_cnt    (dc_context_t* context, int from_server, int64_t seconds);

--- a/deltachat-ffi/src/lib.rs
+++ b/deltachat-ffi/src/lib.rs
@@ -275,7 +275,7 @@ pub unsafe extern "C" fn dc_get_config(
                .strdup()
        } else {
            match config::Config::from_str(&key)
-                .with_context(|| format!("Invalid key {key:?}"))
+                .with_context(|| format!("Invalid key {:?}", &key))
                .log_err(ctx)
            {
                Ok(key) => ctx
--- a/deltachat-jsonrpc/src/api.rs
+++ b/deltachat-jsonrpc/src/api.rs
@@ -735,19 +735,10 @@ impl CommandApi {
        Ok(msg_ids)
    }

-    /// Estimates the number of messages that will be deleted
-    /// by the `set_config()`-option `delete_device_after`.
-    ///
+    /// Estimate the number of messages that will be deleted
+    /// by the set_config()-options `delete_device_after` or `delete_server_after`.
    /// This is typically used to show the estimated impact to the user
    /// before actually enabling deletion of old messages.
-    ///
-    /// Messages in the "Saved Messages" chat are not counted as they will not be deleted automatically.
-    ///
-    /// Parameters:
-    /// - `from_server`: Deprecated, pass `false` here
-    /// - `seconds`: Count messages older than the given number of seconds.
-    ///
-    /// Returns the number of messages that are older than the given number of seconds.
    async fn estimate_auto_deletion_count(
        &self,
        account_id: u32,
--- a/deltachat-repl/src/cmdline.rs
+++ b/deltachat-repl/src/cmdline.rs
@@ -122,7 +122,7 @@ async fn poke_spec(context: &Context, spec: Option<&str>) -> bool {
                let name_f = entry.file_name();
                let name = name_f.to_string_lossy();
                if name.ends_with(".eml") {
-                    let path_plus_name = format!("{real_spec}/{name}");
+                    let path_plus_name = format!("{}/{}", &real_spec, name);
                    println!("Import: {path_plus_name}");
                    if poke_eml_file(context, Path::new(&path_plus_name))
                        .await
@@ -133,11 +133,11 @@ async fn poke_spec(context: &Context, spec: Option<&str>) -> bool {
                }
            }
        } else {
-            eprintln!("Import: Cannot open directory {real_spec:?}.");
+            eprintln!("Import: Cannot open directory \"{}\".", &real_spec);
            return false;
        }
    }
-    println!("Import: {read_cnt} items read from {real_spec:?}.");
+    println!("Import: {} items read from \"{}\".", read_cnt, &real_spec);
    if read_cnt > 0 {
        context.emit_msgs_changed_without_ids();
    }
@@ -179,7 +179,7 @@ async fn log_msg(context: &Context, prefix: impl AsRef<str>, msg: &Message) {
        msg.get_id(),
        if msg.get_showpadlock() { "🔒" } else { "" },
        if msg.has_location() { "📍" } else { "" },
-        contact_name,
+        &contact_name,
        contact_id,
        msgtext,
        if msg.has_html() { "[HAS-HTML]️" } else { "" },
@@ -221,7 +221,7 @@ async fn log_msg(context: &Context, prefix: impl AsRef<str>, msg: &Message) {
        },
        statestr,
        downloadstate,
-        temp2,
+        &temp2,
    );
 }

@@ -561,7 +561,7 @@ pub async fn cmdline(context: Context, line: &str, chat_id: &mut ChatId) -> Resu
                            .map_or_else(String::new, |prefix| format!("{prefix}: ")),
                        summary.text,
                        statestr,
-                        timestr,
+                        &timestr,
                        if chat.is_sending_locations() {
                            "📍"
                        } else {
--- a/deltachat-repl/src/main.rs
+++ b/deltachat-repl/src/main.rs
@@ -432,7 +432,7 @@ async fn handle_cmd(
                {
                    println!("Open the following url, set mail_pw to the generated token and server_flags to 2:\n{oauth2_url}");
                } else {
-                    println!("OAuth2 not available for {addr}.");
+                    println!("OAuth2 not available for {}.", &addr);
                }
            } else {
                println!("oauth2: set addr first.");
--- a/deltachat-rpc-client/README.md
+++ b/deltachat-rpc-client/README.md
@@ -29,7 +29,7 @@ $ pip install .

 1. Build `deltachat-rpc-server` with `cargo build -p deltachat-rpc-server`.
 2. Install tox `pip install -U tox`
-3. Run `CHATMAIL_DOMAIN=ci-chatmail.testrun.org PATH="../target/debug:$PATH" tox`.
+3. Run `CHATMAIL_DOMAIN=nine.testrun.org PATH="../target/debug:$PATH" tox`.

 Additional arguments to `tox` are passed to pytest, e.g. `tox -- -s` does not capture test output.

--- a/deltachat-rpc-client/tests/test_folders.py
+++ b/deltachat-rpc-client/tests/test_folders.py
@@ -14,13 +14,10 @@ def test_moved_markseen(acfactory, direct_imap, log):
    ac2.add_or_update_transport({"addr": addr, "password": password})
    ac2.bring_online()

-    # Make sure that messages are not immediately auto-deleted on the server:
-    ac1.set_config("bcc_self", "1")
-    ac2.set_config("bcc_self", "1")
-
    log.section("ac2: creating DeltaChat folder")
    ac2_direct_imap = direct_imap(ac2)
    ac2_direct_imap.create_folder("DeltaChat")
+    ac2.set_config("delete_server_after", "0")
    ac2.set_config("sync_msgs", "0")  # Do not send a sync message when accepting a contact request.

    ac2.add_or_update_transport({"addr": addr, "password": password, "imapFolder": "DeltaChat"})
@@ -60,9 +57,11 @@ def test_moved_markseen(acfactory, direct_imap, log):
 def test_markseen_message_and_mdn(acfactory, direct_imap):
    ac1, ac2 = acfactory.get_online_accounts(2)

-    # Make sure that messages are not immediately auto-deleted on the server:
-    ac1.set_config("bcc_self", "1")
-    ac2.set_config("bcc_self", "1")
+    for ac in ac1, ac2:
+        ac.set_config("delete_server_after", "0")
+
+    # Do not send BCC to self, we only want to test MDN on ac1.
+    ac1.set_config("bcc_self", "0")

    acfactory.get_accepted_chat(ac1, ac2).send_text("hi")
    msg = ac2.wait_for_incoming_msg()
@@ -82,18 +81,17 @@ def test_markseen_message_and_mdn(acfactory, direct_imap):
    ac1_direct_imap.select_folder("INBOX")
    ac2_direct_imap.select_folder("INBOX")

-    # Check that the mdn and original message is marked as seen
-    assert len(list(ac1_direct_imap.conn.fetch(AND(seen=True), mark_seen=False))) == 2
-    assert len(list(ac2_direct_imap.conn.fetch(AND(seen=True), mark_seen=False))) == 2
+    # Check that the mdn is marked as seen
+    assert len(list(ac1_direct_imap.conn.fetch(AND(seen=True), mark_seen=False))) == 1
+    # Check original message is marked as seen
+    assert len(list(ac2_direct_imap.conn.fetch(AND(seen=True), mark_seen=False))) == 1


 def test_trash_multiple_messages(acfactory, direct_imap, log):
    ac1, ac2 = acfactory.get_online_accounts(2)
    ac2.stop_io()

-    # Make sure that messages are not immediately auto-deleted on the server:
-    ac2.set_config("bcc_self", "1")
-
+    ac2.set_config("delete_server_after", "0")
    ac2.set_config("sync_msgs", "0")

    ac2.start_io()
--- a/deltachat-rpc-client/tests/test_multidevice.py
+++ b/deltachat-rpc-client/tests/test_multidevice.py
@@ -4,29 +4,39 @@ from deltachat_rpc_client import EventType
 from deltachat_rpc_client.const import MessageState


-def test_bcc_self_is_enabled_when_setting_up_second_device(acfactory):
+def test_bcc_self_delete_server_after_defaults(acfactory):
+    """Test default values for bcc_self and delete_server_after."""
    ac = acfactory.get_online_account()

    # Initially after getting online
    # the setting bcc_self is set to 0 because there is only one device
+    # and delete_server_after is "1", meaning immediate deletion.
    assert ac.get_config("bcc_self") == "0"
+    assert ac.get_config("delete_server_after") == "1"

    # Setup a second device.
    ac_clone = ac.clone()
    ac_clone.bring_online()

-    # Second device setup enables bcc_self.
+    # Second device setup
+    # enables bcc_self and changes default delete_server_after.
    assert ac.get_config("bcc_self") == "1"
-    assert ac_clone.get_config("bcc_self") == "1"
+    assert ac.get_config("delete_server_after") == "0"

-    # Test manually disabling bcc_self
+    assert ac_clone.get_config("bcc_self") == "1"
+    assert ac_clone.get_config("delete_server_after") == "0"
+
+    # Manually disabling bcc_self
+    # also restores the default for delete_server_after.
    ac.set_config("bcc_self", "0")
    assert ac.get_config("bcc_self") == "0"
+    assert ac.get_config("delete_server_after") == "1"

-    # Cloning the account again enables bcc_self again
+    # Cloning the account again enables bcc_self
    # even though it was manually disabled.
    ac_clone = ac.clone()
    assert ac.get_config("bcc_self") == "1"
+    assert ac.get_config("delete_server_after") == "0"


 def test_one_account_send_bcc_setting(acfactory, log, direct_imap):
--- a/deltachat-rpc-client/tests/test_something.py
+++ b/deltachat-rpc-client/tests/test_something.py
@@ -1232,12 +1232,11 @@ def test_leave_and_delete_group(acfactory, log):


 def test_immediate_autodelete(acfactory, direct_imap, log):
-    """
-    `bcc_self` is off by default,
-    so that messages are supposed to be immediately autodeleted
-    """
    ac1, ac2 = acfactory.get_online_accounts(2)

+    # "1" means delete immediately, while "0" means do not delete
+    ac2.set_config("delete_server_after", "1")
+
    log.section("ac1: create chat with ac2")
    chat1 = ac1.create_chat(ac2)
    ac2.create_chat(ac1)
--- a/deny.toml
+++ b/deny.toml
@@ -43,12 +43,7 @@ ignore = [
    # hickory-proto 0.25.2 quadratic complexity issue.
    # Dependency of iroh 0.35.0, cannot be updated as of 2026-05-02.
    # <https://rustsec.org/advisories/RUSTSEC-2026-0119>
-    "RUSTSEC-2026-0119",
-
-    # Timing side channel in ml-dsa dependency of rPGP.
-    # We enable PQC for encryption rather than signatures.
-    # <https://rustsec.org/advisories/RUSTSEC-2025-0144>
-    "RUSTSEC-2025-0144",
+    "RUSTSEC-2026-0119"
 ]

 [bans]
@@ -67,7 +62,6 @@ skip = [
     { name = "getrandom", version = "0.2.12" },
     { name = "heck", version = "0.4.1" },
     { name = "http", version = "0.2.12" },
-     { name = "hybrid-array", version = "0.2.3" },
     { name = "linux-raw-sys", version = "0.4.14" },
     { name = "lru", version = "0.12.5" },
     { name = "netlink-packet-route", version = "0.17.1" },
--- a/python/src/deltachat/testplugin.py
+++ b/python/src/deltachat/testplugin.py
@@ -521,6 +521,7 @@ class ACFactory:
        assert "addr" in configdict and "mail_pw" in configdict, configdict
        configdict.setdefault("bcc_self", False)
        configdict.setdefault("sync_msgs", False)
+        configdict.setdefault("delete_server_after", 0)
        ac.update_config(configdict)
        self._acsetup._account2config[ac] = configdict
        self._preconfigure_key(ac)
--- a/python/tests/test_0_complex_or_slow.py
+++ b/python/tests/test_0_complex_or_slow.py
@@ -298,6 +298,73 @@ def test_use_new_verified_group_after_going_online(acfactory, data, tmp_path, lp
    assert msg_in.text == msg_out.text


+def test_verified_group_vs_delete_server_after(acfactory, tmp_path, lp):
+    """Test for the issue #4346:
+    - User is added to a verified group.
+    - First device of the user downloads "member added" from the group.
+    - First device removes "member added" from the server.
+    - Some new messages are sent to the group.
+    - Second device comes online, receives these new messages.
+      The result is an unverified group with unverified members.
+    - First device re-gossips Autocrypt keys to the group.
+    - Now the second device has all members and group verified.
+    """
+    ac1, ac2 = acfactory.get_online_accounts(2)
+    acfactory.remove_preconfigured_keys()
+    ac2_offl = acfactory.new_online_configuring_account(cloned_from=ac2)
+    for ac in [ac2, ac2_offl]:
+        ac.set_config("bcc_self", "1")
+    ac2.set_config("delete_server_after", "1")
+    ac2.set_config("gossip_period", "0")  # Re-gossip in every message
+    acfactory.bring_accounts_online()
+    dir = tmp_path / "exportdir"
+    dir.mkdir()
+    ac2.export_self_keys(str(dir))
+    ac2_offl.import_self_keys(str(dir))
+    ac2_offl.stop_io()
+
+    lp.sec("ac1: create verified-group QR, ac2 scans and joins")
+    chat1 = ac1.create_group_chat("hello")
+    qr = chat1.get_join_qr()
+    lp.sec("ac2: start QR-code based join-group protocol")
+    chat2 = ac2.qr_join_chat(qr)
+    ac1._evtracker.wait_securejoin_inviter_progress(1000)
+    # Wait for "Member Me (<addr>) added by <addr>." message.
+    msg_in = ac2._evtracker.wait_next_incoming_message()
+    assert msg_in.is_system_message()
+
+    lp.sec("ac2: waiting for 'member added' to be deleted on the server")
+    ac2._evtracker.get_matching("DC_EVENT_IMAP_MESSAGE_DELETED")
+
+    lp.sec("ac1: sending 'hi' to the group")
+    ac2.set_config("delete_server_after", "0")
+    chat1.send_text("hi")
+
+    lp.sec("ac2_offl: going online, checking the 'hi' message")
+    ac2_offl.start_io()
+    msg_in = ac2_offl._evtracker.wait_next_incoming_message()
+    assert not msg_in.is_system_message()
+    assert msg_in.text == "hi"
+    ac2_offl_ac1_contact = msg_in.get_sender_contact()
+    assert ac2_offl_ac1_contact.addr == ac1.get_config("addr")
+    assert not ac2_offl_ac1_contact.is_verified()
+    chat2_offl = msg_in.chat
+
+    lp.sec("ac2: sending message re-gossiping Autocrypt keys")
+    chat2.send_text("hi2")
+
+    lp.sec("ac2_offl: receiving message")
+    ev = ac2_offl._evtracker.get_matching("DC_EVENT_INCOMING_MSG|DC_EVENT_MSGS_CHANGED")
+    msg_in = ac2_offl.get_message_by_id(ev.data2)
+    assert not msg_in.is_system_message()
+    assert msg_in.text == "hi2"
+    assert msg_in.chat == chat2_offl
+    assert msg_in.get_sender_contact().addr == ac2.get_config("addr")
+    # Until we reset verifications and then send the _verified header,
+    # verification is not gossiped here:
+    assert not ac2_offl_ac1_contact.is_verified()
+
+
 def test_deleted_msgs_dont_reappear(acfactory):
    ac1 = acfactory.new_online_configuring_account()
    acfactory.bring_accounts_online()
--- a/python/tests/test_1_online.py
+++ b/python/tests/test_1_online.py
@@ -15,9 +15,6 @@ def test_basic_imap_api(acfactory, tmp_path):
    ac1, ac2 = acfactory.get_online_accounts(2)
    chat12 = acfactory.get_accepted_chat(ac1, ac2)

-    # Make sure that messages are not immediately auto-deleted on the server:
-    ac2.set_config("bcc_self", "1")
-
    imap2 = ac2.direct_imap

    with imap2.idle() as idle2:
@@ -165,9 +162,6 @@ def test_webxdc_message(acfactory, data, lp):
    ac1, ac2 = acfactory.get_online_accounts(2)
    chat = acfactory.get_accepted_chat(ac1, ac2)

-    # Make sure that messages are not immediately auto-deleted on the server:
-    ac2.set_config("bcc_self", "1")
-
    lp.sec("ac1: prepare and send text message to ac2")
    msg1 = chat.send_text("message0")
    assert not msg1.is_webxdc()
@@ -368,10 +362,6 @@ def test_send_and_receive_message_markseen(acfactory, lp):
    # make DC's life harder wrt to encodings
    ac1.set_config("displayname", "ä name")

-    # Make sure that messages are not immediately auto-deleted on the server:
-    ac1.set_config("bcc_self", "1")
-    ac2.set_config("bcc_self", "1")
-
    # clear any fresh device messages
    ac1.get_device_chat().mark_noticed()
    ac2.get_device_chat().mark_noticed()
@@ -516,15 +506,9 @@ def test_mdn_asymmetric(acfactory, lp):
    ac1.set_config("mdns_enabled", "1")
    ac2.set_config("mdns_enabled", "1")

-    # Make sure that the mdn is not immediately auto-deleted on the server:
-    ac1.set_config("bcc_self", "1")
-
    lp.sec("sending text message from ac1 to ac2")
    msg_out = chat.send_text("message1")

-    # Wait for the message to be marked as seen on IMAP.
-    ac1._evtracker.get_info_contains("Marked messages [0-9]+ in folder INBOX as seen.")
-
    assert len(chat.get_messages()) == 1 + E2EE_INFO_MSGS

    lp.sec("disable ac1 MDNs")
@@ -541,7 +525,7 @@ def test_mdn_asymmetric(acfactory, lp):
    lp.sec("ac1: waiting for incoming activity")
    assert len(chat.get_messages()) == 1 + E2EE_INFO_MSGS

-    # Wait for the mdn to be marked as seen on IMAP.
+    # Wait for the message to be marked as seen on IMAP.
    ac1._evtracker.get_info_contains("Marked messages [0-9]+ in folder INBOX as seen.")

    # MDN is received even though MDNs are already disabled
@@ -1089,8 +1073,6 @@ def test_send_receive_locations(acfactory, lp):

 def test_delete_multiple_messages(acfactory, lp):
    ac1, ac2 = acfactory.get_online_accounts(2)
-    # Make sure that messages are not immediately auto-deleted on the server:
-    ac2.set_config("bcc_self", "1")
    chat12 = acfactory.get_accepted_chat(ac1, ac2)

    lp.sec("ac1: sending seven messages")
--- a/scripts/update-provider-database.sh
+++ b/scripts/update-provider-database.sh
@@ -6,7 +6,7 @@ set -euo pipefail
 export TZ=UTC

 # Provider database revision.
-REV=2cba4b72f4c6e6417b83ba549aff7781be5f166c
+REV=ad097ee40579c884e7757de2d3bb0a51f481a32a

 CORE_ROOT="$PWD"
 TMP="$(mktemp -d)"
--- a/src/accounts.rs
+++ b/src/accounts.rs
@@ -794,7 +794,7 @@ impl Config {
                .with_push_subscriber(push_subscriber.clone())
                .build()
                .await
-                .with_context(|| format!("failed to create context from file {dbfile:?}"))?;
+                .with_context(|| format!("failed to create context from file {:?}", &dbfile))?;
            // Try to open without a passphrase,
            // but do not return an error if account is passphare-protected.
            ctx.open("".to_string()).await?;
--- a/src/chat.rs
+++ b/src/chat.rs
@@ -2529,7 +2529,7 @@ async fn prepare_msg_blob(context: &Context, msg: &mut Message) -> Result<()> {
        // running numbers, etc.
        let filename: String = match viewtype_orig {
            Viewtype::Voice => format!(
-                "voice-messsage_{}.{suffix}",
+                "voice-messsage_{}.{}",
                chrono::Utc
                    .timestamp_opt(msg.timestamp_sort, 0)
                    .single()
@@ -2537,9 +2537,10 @@ async fn prepare_msg_blob(context: &Context, msg: &mut Message) -> Result<()> {
                        || "YY-mm-dd_hh:mm:ss".to_string(),
                        |ts| ts.format("%Y-%m-%d_%H-%M-%S").to_string()
                    ),
+                &suffix
            ),
            Viewtype::Image | Viewtype::Gif => format!(
-                "image_{}.{suffix}",
+                "image_{}.{}",
                chrono::Utc
                    .timestamp_opt(msg.timestamp_sort, 0)
                    .single()
@@ -2547,9 +2548,10 @@ async fn prepare_msg_blob(context: &Context, msg: &mut Message) -> Result<()> {
                        || "YY-mm-dd_hh:mm:ss".to_string(),
                        |ts| ts.format("%Y-%m-%d_%H-%M-%S").to_string(),
                    ),
+                &suffix,
            ),
            Viewtype::Video => format!(
-                "video_{}.{suffix}",
+                "video_{}.{}",
                chrono::Utc
                    .timestamp_opt(msg.timestamp_sort, 0)
                    .single()
@@ -2557,6 +2559,7 @@ async fn prepare_msg_blob(context: &Context, msg: &mut Message) -> Result<()> {
                        || "YY-mm-dd_hh:mm:ss".to_string(),
                        |ts| ts.format("%Y-%m-%d_%H-%M-%S").to_string()
                    ),
+                &suffix
            ),
            _ => filename,
        };
--- a/src/config.rs
+++ b/src/config.rs
@@ -194,6 +194,17 @@ pub enum Config {
    #[strum(props(default = "0"))] // also change MediaQuality.default() on changes
    MediaQuality,

+    /// Timer in seconds after which the message is deleted from the
+    /// server.
+    ///
+    /// 0 means messages are never deleted by Delta Chat.
+    ///
+    /// Value 1 is treated as "delete at once": messages are deleted
+    /// immediately, without moving to DeltaChat folder.
+    ///
+    /// Default is 1 for chatmail accounts without `BccSelf`, 0 otherwise.
+    DeleteServerAfter,
+
    /// Timer in seconds after which the message is deleted from the
    /// device.
    ///
@@ -543,6 +554,14 @@ impl Context {
        // Default values
        let val = match key {
            Config::ConfiguredInboxFolder => Some("INBOX".to_string()),
+            Config::DeleteServerAfter => {
+                match !Box::pin(self.get_config_bool(Config::BccSelf)).await?
+                    && Box::pin(self.is_chatmail()).await?
+                {
+                    true => Some("1".to_string()),
+                    false => Some("0".to_string()),
+                }
+            }
            Config::Addr => self.get_config_opt(Config::ConfiguredAddr).await?,
            _ => key.get_str("default").map(|s| s.to_string()),
        };
@@ -623,6 +642,23 @@ impl Context {
        self.get_config_bool(Config::MdnsEnabled).await
    }

+    /// Gets configured "delete_server_after" value.
+    ///
+    /// `None` means never delete the message, `Some(0)` means delete
+    /// at once, `Some(x)` means delete after `x` seconds.
+    pub async fn get_config_delete_server_after(&self) -> Result<Option<i64>> {
+        let val = match self
+            .get_config_parsed::<i64>(Config::DeleteServerAfter)
+            .await?
+            .unwrap_or(0)
+        {
+            0 => None,
+            1 => Some(0),
+            x => Some(x),
+        };
+        Ok(val)
+    }
+
    /// Gets the configured provider.
    ///
    /// The provider is determined by the current primary transport.
--- a/src/config/config_tests.rs
+++ b/src/config/config_tests.rs
@@ -142,6 +142,28 @@ async fn test_mdns_default_behaviour() -> Result<()> {
    Ok(())
 }

+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn test_delete_server_after_default() -> Result<()> {
+    let t = &TestContext::new_alice().await;
+
+    // Check that the settings are displayed correctly.
+    assert_eq!(t.get_config(Config::BccSelf).await?, Some("1".to_string()));
+    assert_eq!(
+        t.get_config(Config::DeleteServerAfter).await?,
+        Some("0".to_string())
+    );
+
+    // Leaving emails on the server even w/o `BccSelf` is a good default at least because other
+    // MUAs do so even if the server doesn't save sent messages to some sentbox (like Gmail
+    // does).
+    t.set_config_bool(Config::BccSelf, false).await?;
+    assert_eq!(
+        t.get_config(Config::DeleteServerAfter).await?,
+        Some("0".to_string())
+    );
+    Ok(())
+}
+
 const SAVED_MESSAGES_DEDUPLICATED_FILE: &str = "969142cb84015bc135767bc2370934a.png";

 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
--- a/src/configure.rs
+++ b/src/configure.rs
@@ -707,7 +707,8 @@ async fn get_autoconfig(
        ctx,
        // the doc does not mention `emailaddress=`, however, Thunderbird adds it, see <https://releases.mozilla.org/pub/thunderbird/>,  which makes some sense
        &format!(
-            "https://{param_domain}/.well-known/autoconfig/mail/config-v1.1.xml?emailaddress={param_addr_urlencoded}"
+            "https://{}/.well-known/autoconfig/mail/config-v1.1.xml?emailaddress={}",
+            &param_domain, &param_addr_urlencoded
        ),
        &param.addr,
    )
@@ -720,7 +721,7 @@ async fn get_autoconfig(
    // Outlook uses always SSL but different domains (this comment describes the next two steps)
    if let Ok(res) = outlk_autodiscover(
        ctx,
-        format!("https://{param_domain}/autodiscover/autodiscover.xml"),
+        format!("https://{}/autodiscover/autodiscover.xml", &param_domain),
    )
    .await
    {
@@ -730,7 +731,10 @@ async fn get_autoconfig(

    if let Ok(res) = outlk_autodiscover(
        ctx,
-        format!("https://autodiscover.{param_domain}/autodiscover/autodiscover.xml",),
+        format!(
+            "https://autodiscover.{}/autodiscover/autodiscover.xml",
+            &param_domain
+        ),
    )
    .await
    {
@@ -741,7 +745,7 @@ async fn get_autoconfig(
    // always SSL for Thunderbird's database
    if let Ok(res) = moz_autoconfigure(
        ctx,
-        &format!("https://autoconfig.thunderbird.net/v1.1/{param_domain}"),
+        &format!("https://autoconfig.thunderbird.net/v1.1/{}", &param_domain),
        &param.addr,
    )
    .await
--- a/src/context.rs
+++ b/src/context.rs
@@ -973,6 +973,12 @@ impl Context {
                .await?
                .to_string(),
        );
+        res.insert(
+            "delete_server_after",
+            self.get_config_int(Config::DeleteServerAfter)
+                .await?
+                .to_string(),
+        );
        res.insert(
            "last_housekeeping",
            self.get_config_int(Config::LastHousekeeping)
--- a/src/download.rs
+++ b/src/download.rs
@@ -15,6 +15,12 @@ use crate::{EventType, chatlist_events};
 pub(crate) mod post_msg_metadata;
 pub(crate) use post_msg_metadata::PostMsgMetadata;

+/// If a message is downloaded only partially
+/// and `delete_server_after` is set to small timeouts (eg. "at once"),
+/// the user might have no chance to actually download that message.
+/// `MIN_DELETE_SERVER_AFTER` increases the timeout in this case.
+pub(crate) const MIN_DELETE_SERVER_AFTER: i64 = 48 * 60 * 60;
+
 /// From this point onward outgoing messages are considered large
 /// and get a Pre-Message, which announces the Post-Message.
 /// This is only about sending so we can modify it any time.
--- a/src/ephemeral.rs
+++ b/src/ephemeral.rs
@@ -23,15 +23,16 @@
 //! ## Device settings
 //!
 //! In addition to per-chat ephemeral message setting, each device has
-//! a global user-configured setting that complements per-chat
-//! settings, `delete_device_after`.
-//! This setting is not synchronized among devices and applies to all
+//! two global user-configured settings that complement per-chat
+//! settings: `delete_device_after` and `delete_server_after`. These
+//! settings are not synchronized among devices and apply to all
 //! messages known to the device, including messages sent or received
 //! before configuring the setting.
 //!
 //! `delete_device_after` configures the maximum time device is
-//! storing the messages locally,
-//! but does not delete messages from the server.
+//! storing the messages locally. `delete_server_after` configures the
+//! time after which device will delete the messages it knows about
+//! from the server.
 //!
 //! ## How messages are deleted
 //!
@@ -59,8 +60,9 @@
 //!
 //! Server deletion happens by updating the `imap` table based on
 //! the database entries which are expired either according to their
-//! ephemeral message timers.
+//! ephemeral message timers or global `delete_server_after` setting.

+use std::cmp::max;
 use std::collections::BTreeSet;
 use std::fmt;
 use std::num::ParseIntError;
@@ -73,11 +75,10 @@ use serde::{Deserialize, Serialize};
 use tokio::time::timeout;

 use crate::chat::{ChatId, ChatIdBlocked, send_msg};
-use crate::config::Config;
 use crate::constants::{DC_CHAT_ID_LAST_SPECIAL, DC_CHAT_ID_TRASH};
 use crate::contact::ContactId;
 use crate::context::Context;
-use crate::download::DownloadState;
+use crate::download::MIN_DELETE_SERVER_AFTER;
 use crate::events::EventType;
 use crate::log::{LogExt, warn};
 use crate::message::{Message, MessageState, MsgId, Viewtype};
@@ -650,115 +651,37 @@ pub(crate) async fn ephemeral_loop(context: &Context, interrupt_receiver: Receiv
 }

 /// Schedules expired IMAP messages for deletion.
-pub(crate) async fn delete_expired_imap_messages(
-    context: &Context,
-    transport_id: u32,
-    is_chatmail: bool,
-) -> Result<()> {
+#[expect(clippy::arithmetic_side_effects)]
+pub(crate) async fn delete_expired_imap_messages(context: &Context) -> Result<()> {
    let now = time();

-    if !context.get_config_bool(Config::BccSelf).await? && is_chatmail {
-        info!(
-            context,
-            "dbg marking all as deleted 1 - rfc724_mids: {:?}",
-            context
-                .sql
-                .query_map_vec(
-                    "SELECT rfc724_mid FROM msgs
-                    WHERE (ephemeral_timestamp!=0 AND ephemeral_timestamp<=?)
-                    OR download_state=?",
-                    (now, DownloadState::Done),
-                    |row| Ok(row.get::<_, String>(0)?)
-                )
-                .await
-        );
-        info!(
-            context,
-            "dbg marking all as deleted 1 - pre_rfc724_mids: {:?}",
-            context
-                .sql
-                .query_map_vec(
-                    "SELECT pre_rfc724_mid FROM msgs
-                    WHERE pre_rfc724_mid!=''",
-                    (),
-                    |row| Ok(row.get::<_, String>(0)?)
-                )
-                .await
-        );
-        // This the only device using this relay.
-        // Mark all downloaded messages for deletion, because they are not needed anymore.
-        //
-        // For pre- and post-messages, `rfc724_mid` contains the post-message's Message-Id.
-        // The pre-message's Message-Id is in pre_rfc724_mid, if it exists.
-        //
-        // Pre-messages can be deleted even if the message wasn't fully downloaded yet,
-        // because it's only the post-message that hasn't been downloaded.
-        context
-            .sql
-            .execute(
-                "UPDATE imap
-                SET target=''
-                WHERE transport_id=?1
-                AND rfc724_mid IN (
-                    SELECT rfc724_mid FROM msgs
-                    WHERE (ephemeral_timestamp!=0 AND ephemeral_timestamp<=?2)
-                    OR download_state=?3
-                    UNION
-                    SELECT pre_rfc724_mid FROM msgs
-                    WHERE pre_rfc724_mid!=''
-                )",
-                (transport_id, now, DownloadState::Done),
-            )
-            .await?;
-    } else {
-        info!(
-            context,
-            "dbg marking ephemeral as deleted 1 - rfc724_mids: {:?}",
-            context
-                .sql
-                .query_map_vec(
-                    "SELECT rfc724_mid FROM msgs
-                    WHERE (ephemeral_timestamp!=0 AND ephemeral_timestamp<=?2)",
-                    (transport_id, now),
-                    |row| Ok(row.get::<_, String>(0)?)
-                )
-                .await
-        );
-        info!(
-            context,
-            "dbg marking ephemeral as deleted 1 - pre_rfc724_mids: {:?}",
-            context
-                .sql
-                .query_map_vec(
-                    "SELECT pre_rfc724_mid FROM msgs
-                    WHERE pre_rfc724_mid!=''
-                    AND (ephemeral_timestamp!=0 AND ephemeral_timestamp<=?)",
-                    (now,),
-                    |row| Ok(row.get::<_, String>(0)?)
-                )
-                .await
-        );
-        // There may be other devices using this relay,
-        // either because there is multi-relay or because this is a classical email server.
-        // Only delete expired ephemeral messages.
-        context
-            .sql
-            .execute(
-                "UPDATE imap
-                SET target=''
-                WHERE transport_id=?1
-                AND rfc724_mid IN (
-                    SELECT rfc724_mid FROM msgs
-                    WHERE (ephemeral_timestamp!=0 AND ephemeral_timestamp<=?2)
-                    UNION
-                    SELECT pre_rfc724_mid FROM msgs
-                    WHERE pre_rfc724_mid!=''
-                    AND (ephemeral_timestamp!=0 AND ephemeral_timestamp<=?2)
-                )",
-                (transport_id, now),
-            )
-            .await?;
-    }
+    let (threshold_timestamp, threshold_timestamp_extended) =
+        match context.get_config_delete_server_after().await? {
+            None => (0, 0),
+            Some(delete_server_after) => (
+                match delete_server_after {
+                    // Guarantee immediate deletion.
+                    0 => i64::MAX,
+                    _ => now - delete_server_after,
+                },
+                now - max(delete_server_after, MIN_DELETE_SERVER_AFTER),
+            ),
+        };
+
+    context
+        .sql
+        .execute(
+            "UPDATE imap
+             SET target=''
+             WHERE rfc724_mid IN (
+               SELECT rfc724_mid FROM msgs
+               WHERE ((download_state = 0 AND timestamp < ?) OR
+                      (download_state != 0 AND timestamp < ?) OR
+                      (ephemeral_timestamp != 0 AND ephemeral_timestamp <= ?))
+             )",
+            (threshold_timestamp, threshold_timestamp_extended, now),
+        )
+        .await?;

    Ok(())
 }
--- a/src/ephemeral/ephemeral_tests.rs
+++ b/src/ephemeral/ephemeral_tests.rs
@@ -451,178 +451,105 @@ async fn test_delete_expired_imap_messages() -> Result<()> {
    let t = TestContext::new_alice().await;
    const HOUR: i64 = 60 * 60;
    let now = time();
-    let transport_id: u32 = 1;
-    let other_transport_id: u32 = 2;
-    let uidvalidity = 12345u32;
-
-    async fn is_deleted(context: &Context, mid: &str) -> Result<bool> {
-        Ok(context
-            .sql
-            .count(
-                "SELECT COUNT(*) FROM imap WHERE target='' AND rfc724_mid=?",
-                (mid,),
+    let transport_id = 1;
+    let uidvalidity = 12345;
+    for (id, timestamp, ephemeral_timestamp) in &[
+        (900, now - 2 * HOUR, 0),
+        (1000, now - 23 * HOUR - MIN_DELETE_SERVER_AFTER, 0),
+        (1010, now - 23 * HOUR, 0),
+        (1020, now - 21 * HOUR, 0),
+        (1030, now - 19 * HOUR, 0),
+        (2000, now - 18 * HOUR, now - HOUR),
+        (2020, now - 17 * HOUR, now + HOUR),
+        (3000, now + HOUR, 0),
+    ] {
+        let message_id = id.to_string();
+        t.sql
+               .execute(
+                   "INSERT INTO msgs (id, rfc724_mid, timestamp, ephemeral_timestamp) VALUES (?,?,?,?);",
+                   (id, &message_id, timestamp, ephemeral_timestamp),
+               )
+               .await?;
+        t.sql
+            .execute(
+                "INSERT INTO imap (transport_id, rfc724_mid, folder, uid, target, uidvalidity) VALUES (?, ?,'INBOX',?, 'INBOX', ?);",
+                (transport_id, &message_id, id, uidvalidity),
            )
-            .await?
-            == 1)
+            .await?;
    }

-    async fn reset_targets(context: &Context) {
+    async fn test_marked_for_deletion(context: &Context, id: u32) -> Result<()> {
+        assert_eq!(
+            context
+                .sql
+                .count(
+                    "SELECT COUNT(*) FROM imap WHERE target='' AND rfc724_mid=?",
+                    (id.to_string(),),
+                )
+                .await?,
+            1
+        );
+        Ok(())
+    }
+
+    async fn remove_uid(context: &Context, id: u32) -> Result<()> {
        context
            .sql
-            .execute("UPDATE imap SET target='INBOX'", ())
-            .await
-            .unwrap();
-    }
-
-    // ── Test messages ────────────────────────────────────────────────────────
-    //
-    // (id, rfc724_mid, ephemeral_timestamp, download_state, pre_rfc724_mid)
-    //
-    //  "expired"          – expired ephemeral, no pre-msg
-    //  "no_expire"        – ephemeral_timestamp=0, not Done  → never deleted
-    //  "future"           – future ephemeral, not Done       → never deleted
-    //  "done"             – Done, no ephemeral               → branch 1 only
-    //  "pre_no_expire_*"  – has pre-msg, but no expiry/Done
-    //  "pre_expired_*"    – has pre-msg, expired ephemeral
-    //  "pre_future_*"     – has pre-msg, future ephemeral
-    //  "wrong_tid"        – expired+Done, but wrong transport_id in imap
-    let msgs: &[(&str, i64, DownloadState, &str)] = &[
-        ("expired", now - HOUR, DownloadState::Available, ""),
-        ("no_expire", 0, DownloadState::Available, ""),
-        ("future", now + HOUR, DownloadState::Available, ""),
-        ("done", 0, DownloadState::Done, ""),
-        (
-            "pre_no_expire_post",
-            0,
-            DownloadState::Available,
-            "pre_no_expire_pre",
-        ),
-        (
-            "pre_expired_post",
-            now - HOUR,
-            DownloadState::Available,
-            "pre_expired_pre",
-        ),
-        (
-            "pre_future_post",
-            now + HOUR,
-            DownloadState::Available,
-            "pre_future_pre",
-        ),
-        ("wrong_tid", now - HOUR, DownloadState::Done, ""),
-    ];
-    for (mid, eph_ts, dl_state, pre_mid) in msgs {
-        t.sql
-            .execute(
-                "INSERT INTO msgs \
-                 (rfc724_mid, timestamp, ephemeral_timestamp, download_state, pre_rfc724_mid) \
-                 VALUES (?,?,0,?,?,?)",
-                (*mid, *eph_ts, *dl_state, *pre_mid),
-            )
+            .execute("DELETE FROM imap WHERE rfc724_mid=?", (id.to_string(),))
            .await?;
+        Ok(())
    }

-    // One imap row per mid (including separate rows for pre-messages),
-    // plus "wrong_tid" on a different transport_id.
-    let imap_rows: &[(&str, u32)] = &[
-        ("expired", transport_id),
-        ("no_expire", transport_id),
-        ("future", transport_id),
-        ("done", transport_id),
-        ("pre_no_expire_post", transport_id),
-        ("pre_no_expire_pre", transport_id), // the pre-message's own imap row
-        ("pre_expired_post", transport_id),
-        ("pre_expired_pre", transport_id),
-        ("pre_future_post", transport_id),
-        ("pre_future_pre", transport_id),
-        ("wrong_tid", other_transport_id), // transport_id filter test
-    ];
-    for (i, (mid, tid)) in imap_rows.iter().enumerate() {
+    // This should mark message 2000 for deletion.
+    delete_expired_imap_messages(&t).await?;
+    test_marked_for_deletion(&t, 2000).await?;
+    remove_uid(&t, 2000).await?;
+    // No other messages are marked for deletion.
+    assert_eq!(
        t.sql
-            .execute(
-                "INSERT INTO imap \
-                 (transport_id, rfc724_mid, folder, uid, target, uidvalidity) \
-                 VALUES (?,?,'INBOX',?,'INBOX',?)",
-                (*tid, *mid, (i + 1) as u32, uidvalidity),
-            )
-            .await?;
-    }
+            .count("SELECT COUNT(*) FROM imap WHERE target=''", ())
+            .await?,
+        0
+    );

-    // ── Branch 1: is_chatmail=true, BccSelf=false (default) ─────────────────
-    //
-    // SQL deletes: (ephemeral_timestamp!=0 AND <=now) OR download_state=Done
-    // Pre-messages: ALL with pre_rfc724_mid!='' unconditionally.
-    delete_expired_imap_messages(&t, transport_id, true).await?;
+    t.set_config(Config::DeleteServerAfter, Some(&*(25 * HOUR).to_string()))
+        .await?;
+    delete_expired_imap_messages(&t).await?;
+    test_marked_for_deletion(&t, 1000).await?;

-    // Tests (ephemeral_timestamp!=0 AND ephemeral_timestamp<=now) path.
-    assert!(is_deleted(&t, "expired").await?);
-    // Tests the ephemeral_timestamp!=0 guard: timestamp=0 satisfies <=now but must not match.
-    assert!(!is_deleted(&t, "no_expire").await?);
-    // Tests the ephemeral_timestamp<=now guard.
-    assert!(!is_deleted(&t, "future").await?);
-    // Tests the OR download_state=Done clause.
-    assert!(is_deleted(&t, "done").await?);
-    // Post-message: no expiry, not Done → not deleted.
-    assert!(!is_deleted(&t, "pre_no_expire_post").await?);
-    // Pre-message: deleted unconditionally (tests UNION SELECT pre_rfc724_mid ... WHERE pre_rfc724_mid!='').
-    assert!(is_deleted(&t, "pre_no_expire_pre").await?);
-    // Post-message with expired ephemeral → deleted.
-    assert!(is_deleted(&t, "pre_expired_post").await?);
-    // Pre-message of expired post → deleted (unconditional pre path).
-    assert!(is_deleted(&t, "pre_expired_pre").await?);
-    // Post-message with future ephemeral → not deleted.
-    assert!(!is_deleted(&t, "pre_future_post").await?);
-    // Pre-message of future post → still deleted (branch 1 pre path has NO ephemeral condition).
-    // If the pre UNION clause gains an ephemeral condition, this would wrongly not be deleted.
-    assert!(is_deleted(&t, "pre_future_pre").await?);
-    // Tests transport_id=?1: expired+Done but on wrong transport_id → not deleted.
-    assert!(!is_deleted(&t, "wrong_tid").await?);
+    MsgId::new(1000)
+        .update_download_state(&t, DownloadState::Available)
+        .await?;
+    t.sql
+        .execute("UPDATE imap SET target=folder WHERE rfc724_mid='1000'", ())
+        .await?;
+    delete_expired_imap_messages(&t).await?;
+    test_marked_for_deletion(&t, 1000).await?; // Delete downloadable anyway.
+    remove_uid(&t, 1000).await?;

-    reset_targets(&t).await;
+    t.set_config(Config::DeleteServerAfter, Some(&*(22 * HOUR).to_string()))
+        .await?;
+    delete_expired_imap_messages(&t).await?;
+    test_marked_for_deletion(&t, 1010).await?;
+    t.sql
+        .execute("UPDATE imap SET target=folder WHERE rfc724_mid='1010'", ())
+        .await?;

-    // ── Branch 2: is_chatmail=false ──────────────────────────────────────────
-    //
-    // SQL deletes: ephemeral_timestamp!=0 AND <=now only (no Done).
-    // Pre-messages: only when the post also satisfies the ephemeral condition.
-    delete_expired_imap_messages(&t, transport_id, false).await?;
+    MsgId::new(1010)
+        .update_download_state(&t, DownloadState::Available)
+        .await?;
+    delete_expired_imap_messages(&t).await?;
+    // Keep downloadable for now.
+    assert_eq!(
+        t.sql
+            .count("SELECT COUNT(*) FROM imap WHERE target=''", ())
+            .await?,
+        0
+    );

-    // Expired ephemeral → deleted.
-    assert!(is_deleted(&t, "expired").await?);
-    // ephemeral_timestamp=0 → not deleted (tests !=0 guard in branch 2).
-    assert!(!is_deleted(&t, "no_expire").await?);
-    // Future ephemeral → not deleted (tests <=now guard in branch 2).
-    assert!(!is_deleted(&t, "future").await?);
-    // Done without expired ephemeral → NOT deleted (key branch 1 vs 2 difference).
-    // If download_state=Done were added to branch 2, this would wrongly be deleted.
-    assert!(!is_deleted(&t, "done").await?);
-    // Post-message: no expiry → not deleted.
-    assert!(!is_deleted(&t, "pre_no_expire_post").await?);
-    // Pre-message of non-expiring post → NOT deleted
-    // (tests ephemeral_timestamp!=0 in branch 2's pre subquery).
-    assert!(!is_deleted(&t, "pre_no_expire_pre").await?);
-    // Post-message with expired ephemeral → deleted.
-    assert!(is_deleted(&t, "pre_expired_post").await?);
-    // Pre-message of expired post → deleted (tests full ephemeral condition in pre subquery).
-    assert!(is_deleted(&t, "pre_expired_pre").await?);
-    // Post-message with future ephemeral → not deleted.
-    assert!(!is_deleted(&t, "pre_future_post").await?);
-    // Pre-message of future post → NOT deleted
-    // (tests ephemeral_timestamp<=now in branch 2's pre subquery).
-    // If the <=now guard were removed there, this would wrongly be deleted.
-    assert!(!is_deleted(&t, "pre_future_pre").await?);
-    // Wrong transport_id → not deleted.
-    assert!(!is_deleted(&t, "wrong_tid").await?);
-
-    reset_targets(&t).await;
-
-    // ── BccSelf=true forces branch 2 even when is_chatmail=true ─────────────
-    //
-    // Tests the `!BccSelf` part of the Rust condition.
-    // If `!BccSelf` were dropped, Done would be deleted here (branch 1 behaviour).
-    t.set_config(Config::BccSelf, Some("1")).await?;
-    delete_expired_imap_messages(&t, transport_id, true).await?;
-    assert!(!is_deleted(&t, "done").await?); // must stay on branch 2
-    assert!(is_deleted(&t, "expired").await?); // branch 2 still runs normally
+    t.set_config(Config::DeleteServerAfter, Some("1")).await?;
+    delete_expired_imap_messages(&t).await?;
+    test_marked_for_deletion(&t, 3000).await?;

    Ok(())
 }
--- a/src/imap.rs
+++ b/src/imap.rs
@@ -21,6 +21,9 @@ use futures_lite::FutureExt;
 use ratelimit::Ratelimit;
 use url::Url;

+use crate::calls::{
+    UnresolvedIceServer, create_fallback_ice_servers, create_ice_servers_from_metadata,
+};
 use crate::chat::{self, ChatId, ChatIdBlocked, add_device_msg};
 use crate::chatlist_events;
 use crate::config::Config;
@@ -46,10 +49,6 @@ use crate::tools::{self, create_id, duration_to_str, time};
 use crate::transport::{
    ConfiguredLoginParam, ConfiguredServerLoginParam, prioritize_server_login_params,
 };
-use crate::{
-    calls::{UnresolvedIceServer, create_fallback_ice_servers, create_ice_servers_from_metadata},
-    ephemeral::delete_expired_imap_messages,
-};

 pub(crate) mod capabilities;
 mod client;
@@ -526,12 +525,6 @@ impl Imap {
            context.scheduler.interrupt_ephemeral_task().await;
        }

-        // Mark expired messages for deletion. Note that `delete_expired_imap_messages` is not
-        // not well optimized and should not be called before fetching.
-        delete_expired_imap_messages(context, session.transport_id(), session.is_chatmail())
-            .await
-            .context("delete_expired_imap_messages")?;
-
        session
            .move_delete_messages(context, watch_folder)
            .await
@@ -1052,12 +1045,15 @@ impl Session {
            if target.is_empty() {
                self.delete_message_batch(context, &uid_set, rowid_set)
                    .await
-                    .with_context(|| format!("cannot delete batch of messages {uid_set:?}"))?;
+                    .with_context(|| format!("cannot delete batch of messages {:?}", &uid_set))?;
            } else {
                self.move_message_batch(context, &uid_set, rowid_set, &target)
                    .await
                    .with_context(|| {
-                        format!("cannot move batch of messages {uid_set:?} to folder {target:?}",)
+                        format!(
+                            "cannot move batch of messages {:?} to folder {:?}",
+                            &uid_set, target
+                        )
                    })?;
            }
        }
@@ -1291,10 +1287,9 @@ impl Session {

        for (request_uids, set) in build_sequence_sets(&request_uids)? {
            info!(context, "Starting UID FETCH of message set \"{}\".", set);
-            let mut fetch_responses = self
-                .uid_fetch(&set, BODY_FULL)
-                .await
-                .with_context(|| format!("fetching messages {set} from folder {folder:?}"))?;
+            let mut fetch_responses = self.uid_fetch(&set, BODY_FULL).await.with_context(|| {
+                format!("fetching messages {} from folder \"{}\"", &set, folder)
+            })?;

            // Map from UIDs to unprocessed FETCH results. We put unprocessed FETCH results here
            // when we want to process other messages first.
@@ -1386,21 +1381,6 @@ impl Session {
                    "Passing message UID {} to receive_imf().", request_uid
                );
                let res = receive_imf_inner(context, rfc724_mid, body, is_seen).await;
-
-                // TODO I don't think this code is needed anymore:
-                // // If the message is not needed anymore on the server, mark it for deletion:
-                // if !context.get_config_bool(Config::BccSelf).await? && is_chatmail {
-                //     context
-                //         .sql
-                //         .execute(
-                //             "UPDATE imap SET target='' WHERE rfc724_mid=?",
-                //             (rfc724_mid,),
-                //         )
-                //         .await?;
-                //     context.scheduler.interrupt_inbox().await;
-                // }
-
-                // If there was an error receiving the message, show a device message:
                let received_msg = match res {
                    Err(err) => {
                        warn!(context, "receive_imf error: {err:#}.");
--- a/src/imex.rs
+++ b/src/imex.rs
@@ -980,15 +980,20 @@ mod tests {

        // Check that the settings are displayed correctly.
        assert_eq!(
-            context1.get_config(Config::BccSelf).await?,
+            context1.get_config(Config::DeleteServerAfter).await?,
            Some("0".to_string())
        );
        context1.set_config_bool(Config::IsChatmail, true).await?;
+        assert_eq!(
+            context1.get_config(Config::BccSelf).await?,
+            Some("0".to_string())
+        );
+        assert_eq!(
+            context1.get_config(Config::DeleteServerAfter).await?,
+            Some("1".to_string())
+        );

-        assert_eq!(context1.get_config_bool(Config::IsMuted).await?, false);
-        context1.set_config_bool(Config::IsMuted, true).await?;
-        assert_eq!(context1.get_config_bool(Config::IsMuted).await?, true);
-
+        assert_eq!(context1.get_config_delete_server_after().await?, Some(0));
        imex(context1, ImexMode::ExportBackup, backup_dir.path(), None).await?;
        let _event = context1
            .evtracker
@@ -1005,9 +1010,15 @@ mod tests {
        assert!(context2.is_configured().await?);
        assert!(context2.is_chatmail().await?);
        for ctx in [context1, context2] {
-            // BccSelf should be enabled automatically when exporting a backup
-            assert_eq!(ctx.get_config_bool(Config::BccSelf).await?, true);
-            assert_eq!(ctx.get_config_bool(Config::IsMuted).await?, true);
+            assert_eq!(
+                ctx.get_config(Config::BccSelf).await?,
+                Some("1".to_string())
+            );
+            assert_eq!(
+                ctx.get_config(Config::DeleteServerAfter).await?,
+                Some("0".to_string())
+            );
+            assert_eq!(ctx.get_config_delete_server_after().await?, None);
        }
        Ok(())
    }
--- a/src/key.rs
+++ b/src/key.rs
@@ -570,11 +570,9 @@ pub async fn preconfigure_keypair(context: &Context, secret_data: &str) -> Resul
 pub struct Fingerprint(Vec<u8>);

 impl Fingerprint {
-    /// Creates new fingerprint.
-    ///
-    /// It is 160-bit (20 bytes) for v4 keys and 32 bytes for v6 keys.
+    /// Creates new 160-bit (20 bytes) fingerprint.
    pub fn new(v: Vec<u8>) -> Fingerprint {
-        debug_assert!(v.len() == 20 || v.len() == 32);
+        debug_assert_eq!(v.len(), 20);
        Fingerprint(v)
    }

@@ -627,10 +625,7 @@ impl std::str::FromStr for Fingerprint {
            .filter(|&c| c.is_ascii_hexdigit())
            .collect();
        let v: Vec<u8> = hex::decode(&hex_repr)?;
-        ensure!(
-            v.len() == 20 || v.len() == 32,
-            "wrong fingerprint length: {hex_repr}"
-        );
+        ensure!(v.len() == 20, "wrong fingerprint length: {hex_repr}");
        let fp = Fingerprint::new(v);
        Ok(fp)
    }
--- a/src/message.rs
+++ b/src/message.rs
@@ -222,7 +222,7 @@ SELECT ?1, rfc724_mid, pre_rfc724_mid, timestamp, ?, ? FROM msgs WHERE id=?1
            } else {
                msg.timestamp_sort
            });
-            ret += &format!("Received: {s}");
+            ret += &format!("Received: {}", &s);
            ret += "\n";
        }

@@ -301,7 +301,7 @@ SELECT ?1, rfc724_mid, pre_rfc724_mid, timestamp, ?, ? FROM msgs WHERE id=?1
            ret += "Type: ";
            ret += &format!("{}", msg.viewtype);
            ret += "\n";
-            ret += &format!("Mimetype: {}\n", msg.get_filemime().unwrap_or_default());
+            ret += &format!("Mimetype: {}\n", &msg.get_filemime().unwrap_or_default());
        }
        let w = msg.param.get_int(Param::Width).unwrap_or_default();
        let h = msg.param.get_int(Param::Height).unwrap_or_default();
@@ -2099,52 +2099,63 @@ pub async fn get_request_msg_cnt(context: &Context) -> usize {
 }

 /// Estimates the number of messages that will be deleted
-/// by the `set_config()`-option `delete_device_after`.
+/// by the options `delete_device_after` or `delete_server_after`.
 ///
 /// This is typically used to show the estimated impact to the user
 /// before actually enabling deletion of old messages.
 ///
-/// Messages in the "Saved Messages" chat are not counted as they will not be deleted automatically.
+/// If `from_server` is true,
+/// estimate deletion count for server,
+/// otherwise estimate deletion count for device.
 ///
-/// Parameters:
-/// - `from_server`: Deprecated, pass `false` here
-/// - `seconds`: Count messages older than the given number of seconds.
+/// Count messages older than the given number of `seconds`.
 ///
 /// Returns the number of messages that are older than the given number of seconds.
+/// Messages in the "saved messages" folder are not counted as they will not be deleted automatically.
 #[expect(clippy::arithmetic_side_effects)]
 pub async fn estimate_deletion_cnt(
    context: &Context,
    from_server: bool,
    seconds: i64,
 ) -> Result<usize> {
-    ensure!(
-        !from_server,
-        "The `delete_server_after` config option was removed. You need to pass `false` for `from_server`."
-    );
-
    let self_chat_id = ChatIdBlocked::lookup_by_contact(context, ContactId::SELF)
        .await?
        .map(|c| c.id)
        .unwrap_or_default();
    let threshold_timestamp = time() - seconds;

-    let cnt = context
-        .sql
-        .count(
-            "SELECT COUNT(*)
+    let cnt = if from_server {
+        context
+            .sql
+            .count(
+                "SELECT COUNT(*)
+             FROM msgs m
+             WHERE m.id > ?
+               AND timestamp < ?
+               AND chat_id != ?
+               AND EXISTS (SELECT * FROM imap WHERE rfc724_mid=m.rfc724_mid);",
+                (DC_MSG_ID_LAST_SPECIAL, threshold_timestamp, self_chat_id),
+            )
+            .await?
+    } else {
+        context
+            .sql
+            .count(
+                "SELECT COUNT(*)
             FROM msgs m
             WHERE m.id > ?
               AND timestamp < ?
               AND chat_id != ?
               AND chat_id != ? AND hidden = 0;",
-            (
-                DC_MSG_ID_LAST_SPECIAL,
-                threshold_timestamp,
-                self_chat_id,
-                DC_CHAT_ID_TRASH,
-            ),
-        )
-        .await?;
+                (
+                    DC_MSG_ID_LAST_SPECIAL,
+                    threshold_timestamp,
+                    self_chat_id,
+                    DC_CHAT_ID_TRASH,
+                ),
+            )
+            .await?
+    };
    Ok(cnt)
 }

--- a/src/mimefactory.rs
+++ b/src/mimefactory.rs
@@ -1939,18 +1939,27 @@ pub(crate) fn render_outer_message(
 /// Takes the encrypted part, wraps it in a MimePart,
 /// and sets the appropriate Content-Type for the outer message
 pub(crate) fn wrap_encrypted_part(encrypted: String) -> MimePart<'static> {
-    // XXX: additional newline is needed
-    // to pass filtermail at
-    // <https://github.com/deltachat/chatmail/blob/4d915f9800435bf13057d41af8d708abd34dbfa8/chatmaild/src/chatmaild/filtermail.py#L84-L86>:
-    let encrypted = encrypted + "\n";
-
    MimePart::new(
        "multipart/encrypted; protocol=\"application/pgp-encrypted\"",
        vec![
            // Autocrypt part 1
-            MimePart::new("application/pgp-encrypted", "Version: 1\r\n"),
+            MimePart::new("application/pgp-encrypted", "Version: 1\r\n").header(
+                "Content-Description",
+                mail_builder::headers::raw::Raw::new("PGP/MIME version identification"),
+            ),
            // Autocrypt part 2
-            MimePart::new("application/octet-stream", encrypted),
+            MimePart::new(
+                "application/octet-stream; name=\"encrypted.asc\"",
+                encrypted,
+            )
+            .header(
+                "Content-Description",
+                mail_builder::headers::raw::Raw::new("OpenPGP encrypted message"),
+            )
+            .header(
+                "Content-Disposition",
+                mail_builder::headers::raw::Raw::new("inline; filename=\"encrypted.asc\";"),
+            ),
        ],
    )
 }
--- a/src/mimeparser.rs
+++ b/src/mimeparser.rs
@@ -356,7 +356,7 @@ impl MimeMessage {
        let decrypted_msg; // Decrypted signed OpenPGP message.
        let expected_sender_fingerprint: Option<String>;

-        let (mail, is_encrypted) = match Box::pin(decrypt::decrypt(context, &mail)).await {
+        let (mail, is_encrypted) = match decrypt::decrypt(context, &mail).await {
            Ok(Some((mut msg, expected_sender_fp))) => {
                mail_raw = msg.as_data_vec().unwrap_or_default();

--- a/src/net.rs
+++ b/src/net.rs
@@ -109,8 +109,8 @@ pub(crate) async fn connect_tcp_inner(
 ) -> Result<Pin<Box<TimeoutStream<TcpStream>>>> {
    let tcp_stream = timeout(TIMEOUT, TcpStream::connect(addr))
        .await
-        .with_context(|| format!("Connection to {addr} timed out"))?
-        .with_context(|| format!("Connection to {addr} failed"))?;
+        .context("Connection timeout")?
+        .context("Connection failure")?;

    // Disable Nagle's algorithm.
    tcp_stream.set_nodelay(true)?;
@@ -180,7 +180,7 @@ where
        delay_set.spawn(tokio::time::sleep(delay));
    }

-    let mut all_errors = Vec::new();
+    let mut first_error = None;

    let res = loop {
        if let Some(fut) = futures.next() {
@@ -200,7 +200,7 @@ where
                            }
                            Ok(Err(err)) => {
                                // Some connection attempt failed.
-                                all_errors.push(err);
+                                first_error.get_or_insert(err);
                            }
                            Err(err) => {
                                break Err(err);
@@ -211,11 +211,9 @@ where
                        // Out of connection attempts.
                        //
                        // Break out of the loop and return error.
-                        break if all_errors.is_empty() {
-                            Err(format_err!("No connection attempts were made"))
-                        } else {
-                            Err(format_err!("All connection attempts failed: {}", all_errors.into_iter().map(|err| format!("{err:#}")).collect::<Vec<String>>().join("; ")))
-                        };
+                        break Err(
+                            first_error.unwrap_or_else(|| format_err!("No connection attempts were made"))
+                        );
                    }
                }
            },
--- a/src/pgp.rs
+++ b/src/pgp.rs
@@ -847,41 +847,4 @@ mod tests {
        assert!(merge_openpgp_certificates(alice.clone(), bob.clone()).is_err());
        assert!(merge_openpgp_certificates(bob.clone(), alice.clone()).is_err());
    }
-
-    /// Test PQC support.
-    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-    async fn test_pqc() -> Result<()> {
-        let mut tcm = TestContextManager::new();
-        let alice = &tcm.alice().await;
-        let pqc = &tcm.pqc().await;
-
-        let pqc_received_message = tcm.send_recv_accept(alice, pqc, "Hi!").await;
-        let pqc_chat_id = pqc_received_message.chat_id;
-        let pqc_sent = pqc.send_text(pqc_chat_id, "Hello back!").await;
-
-        let alice_rcvd = alice.recv_msg(&pqc_sent).await;
-        assert_eq!(alice_rcvd.text, "Hello back!");
-
-        Ok(())
-    }
-
-    /// Tests securejoin with inviter using PQC key.
-    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-    async fn test_securejoin_pqc_inviter() {
-        let mut tcm = TestContextManager::new();
-        let alice = &tcm.alice().await;
-        let pqc = &tcm.pqc().await;
-
-        tcm.execute_securejoin(pqc, alice).await;
-    }
-
-    /// Tests securejoin with joiner using PQC key.
-    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
-    async fn test_securejoin_pqc_joiner() {
-        let mut tcm = TestContextManager::new();
-        let pqc = &tcm.pqc().await;
-        let bob = &tcm.bob().await;
-
-        tcm.execute_securejoin(bob, pqc).await;
-    }
 }
--- a/src/provider/data.rs
+++ b/src/provider/data.rs
@@ -890,10 +890,16 @@ static P_NAUTA_CU: Provider = Provider {
        strict_tls: false,
        ..ProviderOptions::new()
    },
-    config_defaults: Some(&[ConfigDefault {
-        key: Config::MediaQuality,
-        value: "1",
-    }]),
+    config_defaults: Some(&[
+        ConfigDefault {
+            key: Config::DeleteServerAfter,
+            value: "1",
+        },
+        ConfigDefault {
+            key: Config::MediaQuality,
+            value: "1",
+        },
+    ]),
    oauth2_authorizer: None,
 };

@@ -2376,4 +2382,4 @@ pub(crate) static PROVIDER_IDS: LazyLock<HashMap<&'static str, &'static Provider
    });

 pub static _PROVIDER_UPDATED: LazyLock<chrono::NaiveDate> =
-    LazyLock::new(|| chrono::NaiveDate::from_ymd_opt(2026, 5, 6).unwrap());
+    LazyLock::new(|| chrono::NaiveDate::from_ymd_opt(2026, 4, 21).unwrap());
--- a/src/qr_code_generator.rs
+++ b/src/qr_code_generator.rs
@@ -332,7 +332,7 @@ fn inner_generate_secure_join_qr_code(
                d.attr("cx", logo_position_x + HALF_LOGO_SIZE)?;
                d.attr("cy", logo_position_y + HALF_LOGO_SIZE)?;
                d.attr("r", HALF_LOGO_SIZE)?;
-                d.attr("style", format!("fill:{color}"))
+                d.attr("style", format!("fill:{}", &color))
            })?;

            let avatar_font_size = LOGO_SIZE * 0.65;
--- a/src/receive_imf.rs
+++ b/src/receive_imf.rs
@@ -902,8 +902,10 @@ UPDATE config SET value=? WHERE keyname='configured_addr' AND value!=?1
    }

    // Get user-configured server deletion
+    let delete_server_after = context.get_config_delete_server_after().await?;
+
    if !received_msg.msg_ids.is_empty() {
-        let target = if received_msg.needs_delete_job {
+        let target = if received_msg.needs_delete_job || delete_server_after == Some(0) {
            Some("".to_string())
        } else {
            None
@@ -3558,7 +3560,12 @@ async fn create_or_lookup_mailinglist_or_broadcast(
            mime_parser.timestamp_sent,
        )
        .await
-        .with_context(|| format!("failed to create mailinglist '{name}' for grpid={listid}",))?;
+        .with_context(|| {
+            format!(
+                "failed to create mailinglist '{}' for grpid={}",
+                &name, &listid
+            )
+        })?;

        if chattype == Chattype::InBroadcast {
            chat::add_to_chat_contacts_table(
--- a/src/receive_imf/receive_imf_tests.rs
+++ b/src/receive_imf/receive_imf_tests.rs
@@ -1976,10 +1976,15 @@ async fn test_no_smtp_job_for_self_chat() -> Result<()> {
    assert!(bob.pop_sent_msg_opt(Duration::ZERO).await.is_none());

    bob.set_config_bool(Config::BccSelf, true).await?;
+    bob.set_config(Config::DeleteServerAfter, Some("1")).await?;
+    let mut msg = Message::new_text("Happy birthday to me".to_string());
+    chat::send_msg(bob, chat_id, &mut msg).await?;
+    assert!(bob.pop_sent_msg_opt(Duration::ZERO).await.is_none());
+
+    bob.set_config(Config::DeleteServerAfter, None).await?;
    let mut msg = Message::new_text("Happy birthday to me".to_string());
    chat::send_msg(bob, chat_id, &mut msg).await?;
    assert!(bob.pop_sent_msg_opt(Duration::ZERO).await.is_some());
-
    Ok(())
 }

--- a/src/scheduler.rs
+++ b/src/scheduler.rs
@@ -15,7 +15,7 @@ use crate::config::Config;
 use crate::contact::{ContactId, RecentlySeenLoop};
 use crate::context::Context;
 use crate::download::{download_known_post_messages_without_pre_message, download_msgs};
-use crate::ephemeral;
+use crate::ephemeral::{self, delete_expired_imap_messages};
 use crate::events::EventType;
 use crate::imap::{Imap, session::Session};
 use crate::location;
@@ -484,6 +484,14 @@ async fn fetch_idle(ctx: &Context, connection: &mut Imap, mut session: Session)
        .await
        .context("fetch_move_delete")?;

+    // Mark expired messages for deletion. Marked messages will be deleted from the server
+    // on the next iteration of `fetch_move_delete`. `delete_expired_imap_messages` is not
+    // called right before `fetch_move_delete` because it is not well optimized and would
+    // otherwise slow down message fetching.
+    delete_expired_imap_messages(ctx)
+        .await
+        .context("delete_expired_imap_messages")?;
+
    download_known_post_messages_without_pre_message(ctx, &mut session).await?;
    download_msgs(ctx, &mut session)
        .await
--- a/src/scheduler/connectivity.rs
+++ b/src/scheduler/connectivity.rs
@@ -218,7 +218,7 @@ pub(crate) fn maybe_network_lost(context: &Context, stores: Vec<ConnectivityStor
 impl fmt::Debug for ConnectivityStore {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        if let Some(guard) = self.0.try_lock() {
-            write!(f, "ConnectivityStore {:?}", *guard)
+            write!(f, "ConnectivityStore {:?}", &*guard)
        } else {
            write!(f, "ConnectivityStore [LOCKED]")
        }
--- a/src/securejoin.rs
+++ b/src/securejoin.rs
@@ -73,7 +73,8 @@ fn shorten_name(name: &str, length: usize) -> String {
        // We use _ rather than ... to avoid dots at the end of the URL, which would confuse linkifiers
        format!(
            "{}_",
-            name.chars()
+            &name
+                .chars()
                .take(length.saturating_sub(1))
                .collect::<String>()
        )
--- a/src/securejoin/securejoin_tests.rs
+++ b/src/securejoin/securejoin_tests.rs
@@ -992,7 +992,7 @@ async fn test_wrong_auth_token() -> Result<()> {
    tcm.send_recv(alice, bob, "hi").await;

    let alice_qr = get_securejoin_qr(alice, None).await?;
-    println!("{alice_qr}");
+    println!("{}", &alice_qr);
    let invalid_alice_qr = alice_qr.replace("&s=", "&s=INVALIDAUTHTOKEN&someotherkey=");

    join_securejoin(bob, &invalid_alice_qr).await?;
--- a/src/smtp.rs
+++ b/src/smtp.rs
@@ -699,22 +699,26 @@ pub(crate) async fn add_self_recipients(
    recipients: &mut Vec<String>,
    encrypted: bool,
 ) -> Result<()> {
-    // Avoid sending unencrypted messages to all transports, chatmail relays won't accept
-    // them. Normally the user should have a non-chatmail primary transport to send unencrypted
-    // messages.
-    if encrypted {
-        for addr in context.get_published_secondary_self_addrs().await? {
-            recipients.push(addr);
+    // Previous versions of Delta Chat did not send BCC self
+    // if DeleteServerAfter was set to immediately delete messages
+    // from the server. This is not the case anymore
+    // because BCC-self messages are also used to detect
+    // that message was sent if SMTP server is slow to respond
+    // and connection is frequently lost
+    // before receiving status line. NB: This is not a problem for chatmail servers, so `BccSelf`
+    // disabled by default is fine.
+    if context.get_config_delete_server_after().await? != Some(0) || !recipients.is_empty() {
+        // Avoid sending unencrypted messages to all transports, chatmail relays won't accept
+        // them. Normally the user should have a non-chatmail primary transport to send unencrypted
+        // messages.
+        if encrypted {
+            for addr in context.get_published_secondary_self_addrs().await? {
+                recipients.push(addr);
+            }
        }
+        // `from` must be the last addr, see `receive_imf_inner()` why.
+        let from = context.get_primary_self_addr().await?;
+        recipients.push(from);
    }
-    // `from` must be the last addr
-    // because `receive_imf_inner()` marks the message as 'delivered'
-    // if it arrives to the self-server via `bcc_self`.
-    // This helps with marking messages as delivered
-    // if the server is slow and we never get an `OK` response
-    // before the connection times out.
-    let from = context.get_primary_self_addr().await?;
-    recipients.push(from);
-
    Ok(())
 }
--- a/src/test_utils.rs
+++ b/src/test_utils.rs
@@ -137,17 +137,6 @@ impl TestContextManager {
            .await
    }

-    /// Returns a new "device" with a preconfigured v6 PQC key.
-    pub async fn pqc(&mut self) -> TestContext {
-        TestContext::builder()
-            .with_key_pair(pqc_keypair())
-            .with_address("pqc@example.org".to_string())
-            .with_id_offset(7000)
-            .with_log_sink(self.log_sink.clone())
-            .build(Some(&mut self.used_names))
-            .await
-    }
-
    /// Creates a new unconfigured test account.
    pub async fn unconfigured(&mut self) -> TestContext {
        TestContext::builder()
@@ -315,9 +304,6 @@ impl TestContextManager {
 pub struct TestContextBuilder {
    key_pair: Option<SignedSecretKey>,

-    /// Email address.
-    address: Option<String>,
-
    /// Log sink if set.
    ///
    /// If log sink is not set,
@@ -342,7 +328,6 @@ impl TestContextBuilder {
    /// This is a shortcut for `.with_key_pair(alice_keypair())`.
    pub fn configure_alice(self) -> Self {
        self.with_key_pair(alice_keypair())
-            .with_address("alice@example.org".to_string())
    }

    /// Configures as bob@example.net with fixed secret key.
@@ -350,7 +335,6 @@ impl TestContextBuilder {
    /// This is a shortcut for `.with_key_pair(bob_keypair())`.
    pub fn configure_bob(self) -> Self {
        self.with_key_pair(bob_keypair())
-            .with_address("bob@example.net".to_string())
    }

    /// Configures as charlie@example.net with fixed secret key.
@@ -358,7 +342,6 @@ impl TestContextBuilder {
    /// This is a shortcut for `.with_key_pair(charlie_keypair())`.
    pub fn configure_charlie(self) -> Self {
        self.with_key_pair(charlie_keypair())
-            .with_address("charlie@example.net".to_string())
    }

    /// Configures as dom@example.net with fixed secret key.
@@ -366,7 +349,6 @@ impl TestContextBuilder {
    /// This is a shortcut for `.with_key_pair(dom_keypair())`.
    pub fn configure_dom(self) -> Self {
        self.with_key_pair(dom_keypair())
-            .with_address("dom@example.net".to_string())
    }

    /// Configures as elena@example.net with fixed secret key.
@@ -374,7 +356,6 @@ impl TestContextBuilder {
    /// This is a shortcut for `.with_key_pair(elena_keypair())`.
    pub fn configure_elena(self) -> Self {
        self.with_key_pair(elena_keypair())
-            .with_address("elena@example.net".to_string())
    }

    /// Configures as fiona@example.net with fixed secret key.
@@ -382,7 +363,6 @@ impl TestContextBuilder {
    /// This is a shortcut for `.with_key_pair(fiona_keypair())`.
    pub fn configure_fiona(self) -> Self {
        self.with_key_pair(fiona_keypair())
-            .with_address("fiona@example.net".to_string())
    }

    /// Configures the new [`TestContext`] with the provided [`SignedSecretKey`].
@@ -394,12 +374,6 @@ impl TestContextBuilder {
        self
    }

-    /// Sets email address.
-    pub fn with_address(mut self, address: String) -> Self {
-        self.address = Some(address);
-        self
-    }
-
    /// Attaches a [`LogSink`] to this [`TestContext`].
    ///
    /// This is useful when using multiple [`TestContext`] instances in one test: it allows
@@ -422,7 +396,16 @@ impl TestContextBuilder {
    /// Builds the [`TestContext`].
    pub async fn build(self, used_names: Option<&mut BTreeSet<String>>) -> TestContext {
        if let Some(key_pair) = self.key_pair {
-            let addr = self.address.expect("Address is not set").clone();
+            let userid = {
+                let public_key = key_pair.to_public_key();
+                let id_bstr = public_key.details.users.first().unwrap().id.id();
+                String::from_utf8(id_bstr.to_vec()).unwrap()
+            };
+            let addr = mailparse::addrparse(&userid)
+                .unwrap()
+                .extract_single_info()
+                .unwrap()
+                .addr;
            let name = EmailAddress::new(&addr).unwrap().local;

            let mut unused_name = name.clone();
@@ -1437,13 +1420,6 @@ pub fn fiona_keypair() -> SignedSecretKey {
    key::SignedSecretKey::from_asc(include_str!("../test-data/key/fiona-secret.asc")).unwrap()
 }

-/// Loads a pre-generated v6 PQC keypair from disk.
-///
-/// Like [alice_keypair] but a different key and identity.
-pub fn pqc_keypair() -> SignedSecretKey {
-    key::SignedSecretKey::from_asc(include_str!("../test-data/key/pqc-secret.asc")).unwrap()
-}
-
 /// Utility to help wait for and retrieve events.
 ///
 /// This buffers the events in order they are emitted.  This allows consuming events in
@@ -1707,7 +1683,7 @@ async fn write_msg(context: &Context, prefix: &str, msg: &Message, buf: &mut Str
        msg.get_id(),
        if msg.get_showpadlock() { "🔒" } else { "" },
        if msg.has_location() { "📍" } else { "" },
-        contact_name,
+        &contact_name,
        contact_id,
        msgtext,
        if msg.get_from_id() == ContactId::SELF {
--- a/src/tests/aeap.rs
+++ b/src/tests/aeap.rs
@@ -161,7 +161,7 @@ async fn check_that_transition_worked(
            2,
            "Group {} has members {:?}, but should have members {:?} and {:?}",
            group,
-            members,
+            &members,
            alice_contact_id,
            ContactId::SELF
        );
--- a/src/tools.rs
+++ b/src/tools.rs
@@ -62,13 +62,13 @@ pub(crate) fn truncate(buf: &str, approx_chars: usize) -> Cow<'_, str> {
    if let Some(index) = buf.get(..end_pos).and_then(|s| s.rfind([' ', '\n'])) {
        Cow::Owned(format!(
            "{}{}",
-            buf.get(..=index).unwrap_or_default(),
+            &buf.get(..=index).unwrap_or_default(),
            DC_ELLIPSIS
        ))
    } else {
        Cow::Owned(format!(
            "{}{}",
-            buf.get(..end_pos).unwrap_or_default(),
+            &buf.get(..end_pos).unwrap_or_default(),
            DC_ELLIPSIS
        ))
    }
--- a/src/tools/tools_tests.rs
+++ b/src/tools/tools_tests.rs
@@ -247,12 +247,12 @@ proptest! {
        assert!(
            l <= approx_chars + el_len,
            "buf: '{}' - res: '{}' - len {}, approx {}",
-            buf, res, res.len(), approx_chars
+            &buf, &res, res.len(), approx_chars
        );

        if buf.chars().count() > approx_chars + el_len {
            let l = res.len();
-            assert_eq!(&res[l-5..l], "[...]", "missing ellipsis in {res}");
+            assert_eq!(&res[l-5..l], "[...]", "missing ellipsis in {}", &res);
        }
    }
 }
--- a/src/transport.rs
+++ b/src/transport.rs
@@ -116,7 +116,7 @@ pub(crate) struct ConnectionCandidate {

 impl fmt::Display for ConnectionCandidate {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}:{}:{}", self.host, self.port, self.security)?;
+        write!(f, "{}:{}:{}", &self.host, self.port, self.security)?;
        Ok(())
    }
 }
@@ -131,7 +131,7 @@ pub(crate) struct ConfiguredServerLoginParam {

 impl fmt::Display for ConfiguredServerLoginParam {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}:{}", self.connection, self.user)?;
+        write!(f, "{}:{}", self.connection, &self.user)?;
        Ok(())
    }
 }
--- a/test-data/key/pqc-secret.asc
+++ b/test-data/key/pqc-secret.asc
@@ -1,39 +0,0 @@
-----BEGIN PGP PRIVATE KEY BLOCK-----
-
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-----END PGP PRIVATE KEY BLOCK-----