One flag gated both showing a window and emitting to it, so the fallback timer
set it for a frontend that had not subscribed yet: the queued events were
flushed into a window that could not hear them, losing the login trigger and
the settings tab selection.
Showing is now gated on painted and emitting on mounted, and only a real
frontend report sets mounted. The fallback timer also moved to its own helper
so the runtime-ready hook can rearm it, giving the frontend a full budget to
mount rather than sharing one with webview boot.
Zoltán Papp
ec0b4fb03e