eb52328857
Glass was macOS-only because it rode setVibrancy. Windows 11 22H2 has a first-party equivalent in setBackgroundMaterial, so the mode now resolves its backing per platform instead of per-OS-check: macOS keeps vibrancy, Windows 11 gets DWM acrylic / tabbed / mica, and everything older stays on Clear. No third-party native addon. Two Windows-specific details the mapping has to respect. DWM only paints the client area of a transparent window (electron#49443), so glass-capable Windows chat windows are born transparent with the opaque themed backgroundColor covering them while glass is off — a live Clear/Glass toggle then needs no window recreate. And Windows exposes three backdrops for four frost rungs, so the two heaviest both resolve to mica; the mapping stays total so a frost saved on a Mac still renders. Glass support is computed once from os.release() and shared: main uses it for the persisted default and every window, preload publishes it to the renderer so the UI can't offer a mode the window can't back.