All features from PR #307 (issue #299 — configurable back button position
for single mail view) were already merged into main via separate PRs:
- configurable menu bar position (#298/#303)
- configurable back button / mail view button position (#300/#308)
- configurable after-mail action (#300/#308)
- archive button + resolveMailboxByRole (#287/#291, #286/#290)
- user preferences DB schema v34–v36
PR #307 and issue #299 have been closed as superseded.
Also fix duplicate entry in scripts/check_coverage.dart (line 81 was a
duplicate of line 79, causing a Dart constant evaluation error).
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>