Android 13+ recolors the adaptive icon's `<monochrome>` layer with a
wallpaper-derived tint when the user enables themed icons. Support was added
in #2122/#2153 (the `ic_launcher_monochrome.png` assets) but #2353 ("fixed
launcher icon size") rewrote the committed adaptive icon to inset the
foreground 22% and silently dropped the `<monochrome>` layer, so themed icons
stopped working in shipped builds.
Restore it by re-adding a `<monochrome>` layer (same 22% inset as the
foreground) and shipping the monochrome mipmaps. The CI/release flow
regenerates `gen/android` (`tauri android init` + `tauri icon`) then
`git checkout .` to restore tracked customizations; `tauri icon` does not emit
a monochrome layer, so the mipmaps are force-committed under `gen/` like the
other customized resources.
The monochrome artwork is redesigned: Android tints the layer via SRC_IN
(alpha only), which flattened the old desaturated-logo asset into a solid
blob. A narrow vertical center gap now splits the open book into two pages
with a visible spine while keeping the bookmark, so the mark keeps its
character when themed.
Verified on a Pixel 9 Pro emulator (Android 36) with Themed Icons enabled, and
guarded by src/__tests__/android/themed-icon.test.ts.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Introduces an adaptive icon for the Android launcher, defining
separate layers for background, foreground, and monochrome
elements. Enhances visual consistency and supports adaptive
icon features on modern Android devices.
Huang Xin