His startup.log stops after 'data dir ok', which rules out the two faults
already covered and leaves the window creation itself — where a missing
WebView2 runtime lands, sometimes as a silent exit rather than an error
anyone can print.
So the runtime's version is read from where it registers itself (both
hives, and the 32-bit view where a per-machine install usually lands) and
written BEFORE the window is attempted: 'WebView2: not found' answers the
whole question in one line. Breadcrumbs now also mark entering wails.Run,
reaching OnStartup, and the window painting — which places any launch
that produces nothing between two known points.
