- Compensate for the difference between font ascent used by RichText layout
and the character-size baseline used by Text rendering. Cache the natural
baseline in each text span while preserving background and selection boxes.
- Add pixel-level coverage for proportional and monospace fonts at matching
and different sizes, with default and explicit line heights. Refresh the
affected rendering reference images.
- Keep diff view select buttons last in the child list so lazily created
image viewers cannot intercept their clicks.
- Display source images and generated diffs at native pixel dimensions,
independent of UI density, scaling down only to fit the viewport. Avoid
rounding twice at fractional densities.
- Add regression coverage for mode switching and sizing at densities
1, 1.5, and 2. Use portable temporary paths.