After crash, cannot finish startup until logout&logon

audacity ubuntu LTS 18.04
2.3.3-0build1 from
ubuntuhandbook1/audacity ppa

this is the terminal output

> audacity

(Audacity:11163): Gnome-WARNING **: 07:31:26.189: Accessibility: failed to find module 'libgail-gnome' which is needed to make this application accessible

(Audacity:11163): Gtk-WARNING **: 07:31:26.190: gtk_disable_setlocale() must be called before gtk_init()

what could be the cause? does audacity interface with something else that has to be reset before it can work again?
also often I see audacity complaining about the lock-file,

  • though other instances of audacity aren’t running,
    i guess audacity should detect that no other instances of audacity are running/exist
    and perhaps verify that environment’s state is clear and remove that file

When Audacity runs, it creates a file
/var/tmp/audacity-/audacity-lock-
(where is your user name)

That file is to ensure that there is only one instance of Audacity running at a time.
The file is normally deleted when Audacity quits, though it is possible for it to not be deleted if Audacity crashes. That is not normally a problem, as it contains a unique number, so even if it is left over, it should be deleted and a new lock file created.

It’s a mystery to me why a current version of Audacity would complain about that, but if Audacity is not running, then it is safe to delete that file manually.

After attempting to start audacity for the first time in seven months, I encountered the dreaded “The system has detected that another copy of Audacity is running” error message. Further investigation shows that the “unique number” you speak of is actually a PID. It looks like audacity checks for existence of a process with that PID, but not whether it actually is an audacity process (instead of, as in my case, chromium). :-1:

(audacity 2.3.3-1 (though I had the same problem with 2.2.2) on Debian buster)

Oh dear, that was unlucky. I’ve never previously seen that happen, but it’s easy to prove that it can occur.
I’ll log this issue on Audacity’s issue tracker.

Done.
We already had the issue logged for macOS (where the issue is more easily repeatable), so I’ve added the info about Linux. Thanks miiichael for the additional details.