I can't reproduce the hang with MuseScore 1.0 but I don't get your step 4. If you want to debug a script, launch a plugin.
Some plugins have a hook to be executed when MuseScore stops, that why the script debugger appears if you stop MuseScore.
Script debugger being a (very) advanced feature, I put this bug as minor.
Comments
I can't reproduce the hang with MuseScore 1.0 but I don't get your step 4. If you want to debug a script, launch a plugin.
Some plugins have a hook to be executed when MuseScore stops, that why the script debugger appears if you stop MuseScore.
Script debugger being a (very) advanced feature, I put this bug as minor.
I was just wondering what Script Debugger was (never used it) and encountered this problem when I went to quit.
It was marked critical because a hang is equal to a crash.
The hang is on purpose. The debugger stops MuseScore execution to be able to debug the plugins.