On macOS 11 and 12 other apps keep using the system's built-in WebKit (Safari 14.1 / 15.x) even after Safari is updated, so the Safari 16 interface could not start there. The bundle now declares macOS 13 as its minimum, the install docs say macOS 13, and the startup failure page no longer suggests updating Safari.
Fixes#2008
Failures while the app loads left only the splash, with nothing to report. Handlers in public/boot.js now load before the module graph and replace the splash with an error page with copyable diagnostics and a report link, for module load errors, rejected startup, initial render errors and a 30-second timeout. A successful start cancels the timer.
The production build also rejects selected newer startup APIs and unsupported regex and import syntax. The original macOS 11 trigger remains unconfirmed.
Refs #2008
l0ng-ai