Ran into this a few times, seems worth tracking in case it's unintended.
Hitting a JUCE assert in parseAbsolutePath of juce_File.cpp, note the AU "path" in the screenshot:

This is for an existing AU plugin which for some reason can't be located.
killall -9 AudioComponentRegistrar resolves for me, since the plugin should be registered.
The behavior is different than before, I think, when we used to get an error in the output/UI that no types were found?