A preview guest that HTML5-fullscreens itself owns all input: the host
renderer can't see into the out-of-process webview, the macOS-only Close
menu and HUD chords aren't reachable, and Wayland has no xdotool/wmctrl to
break out from a terminal — so a page that swallows Esc locks the display
(#97213).
Three layers, all routed before the guest sees the key or fully outside it:
- before-input-event on every webview guest: Esc exits the host window's
fullscreen (gated on the fullscreen state so normal-mode panes keep Esc),
Ctrl/Cmd+Shift+W closes the pane via the existing close-preview channel
- hermes://close-preview deep link handled in the main process: restores
and focuses the window, exits fullscreen, closes the pane
- `hermes desktop --close-preview` CLI flag forwarded to the packaged exe,
riding the single-instance argv so a second invocation unlocks the running
app
The permission handlers keep auto-allowing 'fullscreen' — the exit paths
are the fix, and scoping the grant would just break video fullscreen.
Refs #97213
d2b9a49e63