Repository navigation
Fixes photos missing from received mentions in the macOS and Windows desktop apps while the same photos were visible on web and iPhone. The desktop sync snapshot now retains attachments on the task and its subtasks, including the downloaded local file identifiers needed for display, preview and copying.
The regression check now passes mention photos through the production snapshot serializer before sending them to the app window, so it covers the data boundary that previously dropped them.
Validation: 44 unit checks and 22 desktop scenarios. Includes universal macOS and Windows x64 installers and updater feeds. Native iOS remains 1.3.18 (8); this fixes desktop-only code.
The current macOS ad-hoc signature may require manual installation when automatic installation is rejected by macOS.