A "Background dots" slider under Map layers sets how strongly the dot grid
draws behind the map, the library, and exported screenshots and videos.
100% is today's look; 0% hides the grid. The value is a new AppPreferences
field (index 19) that defaults to 1.0, so preferences saved by older builds
load unchanged.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>