So Vegas (12) "has stopped working", which is fine, because as usual I'd quit Vegas a few seconds before it told me it stopped working. But this time when I started Vegas it launched the error reporter before Vegas started (possibly because I'd put the computer to sleep after quitting Vegas but before Vegas had a chance to tell me it had stopped working), which stopped Vegas from loading. But Vegas starts loading before the error reporter kicks in, and when I quickly killed the error report process in Task Manager as soon as it showed, Vegas started normally (and ran with just the normal random crashes). Elementary, but might save someone restarting the system/reloading Vegas from scratch.