When Classical Extras (2.0.12) plug-in is enabled, Picard (2.7.1) will crash any time an album is loaded - either from within the app, or when using the "Tagger" icon from the MusicBrainz website.

The main / right part of Picard will correctly display the "[loading album information]" while the look-up is in process. However if Classical Extras is active, Picard crashes in the instant that the album name appears.

After a bit of experimentation, I found (appropriately) a simple 1-track album that won't cause Picard to crash. Here's the relevant section of the log, with the rest of the log attached.

After attempting to add more complex albums, Picard crashed as I've been experiencing regularly. The Mac Console log of the crash from a more complex album is attached. I'm unable to save the Log from within Picard after it crashes, obviously...as the Log resets itself after each new launch.

D: 14:25:07,806 coverart/{}init{}.next_in_queue:153: Skipping cover art provider Local Files ...

W: 14:25:07,813 /Users/RPM/Library/Preferences/MusicBrainz/Picard/plugins/classical_extras.zip/classical_extras/{}init{}.write_log:247: Classical Extras: No file with matching trackid for track <Track 0645383c-6218-4867-9ca9-964e50d54130 'All I Want for Christmas Is You (extra festive)'>. IF THERE SHOULD BE ONE, TRY 'REFRESH'

E: 14:25:07,814 /Users/RPM/Library/Preferences/MusicBrainz/Picard/plugins/classical_extras.zip/classical_extras/{}init{}.write_log:256: Classical Extras: Work Parts. Failure to read saved options for track <Track 0645383c-6218-4867-9ca9-964e50d54130 'All I Want for Christmas Is You (extra festivehttps://tickets.metabrainz.org/secure/CreateIssue.jspa?pid=10042&issuetype=1#)'>. options =

E: 14:25:07,829 ui/item.error_append:107: <Album 3bba2f53-6750-4b34-a86e-17cff0a5ac02 ''>: Traceback (most recent call last):

File "album.py", line 456, in _finalize_loading_track

File "metadata.py", line 628, in run_track_metadata_processors

File "plugin.py", line 257, in run

File "/Users/RPM/Library/Preferences/MusicBrainz/Picard/plugins/classical_extras.zip/classical_extras/{}init{}.py", line 4258, in add_work_info

get_aliases(self, release_id, album, options, releaseXmlNode)

File "/Users/RPM/Library/Preferences/MusicBrainz/Picard/plugins/classical_extras.zip/classical_extras/{}init{}.py", line 1042, in get_aliases

lang = locale.split("_")[0] # NB this is the Picard code in /util

AttributeError: 'NoneType' object has no attribute 'split'

D: 14:25:07,832 ui/mainwindow.set_statusbar_message:466: Album 3bba2f53-6750-4b34-a86e-17cff0a5ac02 loaded: Mariah Carey - All I Want for Christmas Is You (extra festive)

D: 14:25:07,833 webservice/ratecontrol._out_of_backoff:222: ('musicbrainz.org', 443): oobackoff; delay: 1000ms -> 1000ms; slow start; window size 10.000 -> 11.000