Saved themes now remember everything you set — and they come back exactly that way after a restart.
Your saved theme's background is remembered again — including video backgrounds. A saved theme stores each asset (background image or video, and mask) as a symlink into your data folder rather than a copy, so nothing is duplicated and a video background now plays back when you reload the theme instead of showing nothing. The only real file a saved theme keeps is its own layout (the overlay you edited in settings), rewritten each time you save.
Restarting the app brings back the last theme you were using — with your changes. On launch the app restores the exact theme you last had on each device, along with its background, mask, and overlay edits, instead of falling back to the shipped default. Your own saved theme and a shipped theme that share a name now coexist — saving never overwrites the original, and shipped themes simply list first.
Rotating the display no longer wipes your edits. Changing orientation keeps your overlay layout, background, and mask, matching the original Windows app's behaviour (it rotates what's on screen rather than reloading from scratch).