Root cause: lib.rs applies a Mica backdrop to the main window at startup;
set_custom_chrome then stripped the frame with set_decorations(false), and
Mica + frameless is a broken combination on Windows (DWM backdrop glitches
the whole surface).
- set_custom_chrome: clear_mica() before undecorating, re-apply_mica() when
restoring the native frame; set_shadow(true) so the frameless window keeps
its drop shadow + resize borders.
- window-state plugin: exclude StateFlags::DECORATIONS — the chrome toggle
owns the decorated flag; restoring a saved decorated=false at startup would
recreate the Mica-on-frameless glitch before the web side loads.
Pairs with the web-side TitleBar drag fix (explicit window_start_drag on
mousedown instead of data-tauri-drag-region) in the cinny repo.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
jared
e8fba393f0