diff --git a/python/tests/test_1_online.py b/python/tests/test_1_online.py
index 412247cbb..1d86e8853 100644
--- a/python/tests/test_1_online.py
+++ b/python/tests/test_1_online.py
@@ -134,22 +134,27 @@ def test_one_account_send_bcc_setting(acfactory, lp):
     ac1.set_config("bcc_self", "1")
 
     lp.sec("send out message with bcc to ourselves")
-    with ac1.direct_imap.idle() as idle1:
-        msg_out = chat.send_text("message2")
+    msg_out = chat.send_text("message2")
 
-        # wait for send out (BCC)
-        ev = ac1._evtracker.get_matching("DC_EVENT_SMTP_MESSAGE_SENT")
-        assert ac1.get_config("bcc_self") == "1"
+    # wait for send out (BCC)
+    ev = ac1._evtracker.get_matching("DC_EVENT_SMTP_MESSAGE_SENT")
+    assert ac1.get_config("bcc_self") == "1"
 
-        # now make sure we are sending message to ourselves too
-        assert self_addr in ev.data2
-        assert other_addr in ev.data2
-        assert idle1.wait_for_seen()
-
-    # Second client receives only second message, but not the first
+    # Second client receives only second message, but not the first.
     ev_msg = ac1_clone._evtracker.wait_next_messages_changed()
     assert ev_msg.text == msg_out.text
 
+    # now make sure we are sending message to ourselves too
+    assert self_addr in ev.data2
+    assert other_addr in ev.data2
+
+    # BCC-self messages are marked as seen by the sender device.
+    ac1._evtracker.get_info_contains("Marked messages 1 in folder INBOX as seen.")
+
+    # Check that the message is marked as seen on IMAP.
+    ac1.direct_imap.select_folder("Inbox")
+    assert len(list(ac1.direct_imap.conn.fetch(AND(seen=True)))) == 1
+
 
 def test_send_file_twice_unicode_filename_mangling(tmpdir, acfactory, lp):
     ac1, ac2 = acfactory.get_online_accounts(2)