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The recent upgrade to Picard v1.3 breaks the ability to lookup CDs. Upstream, they have moved to using python-discid instead of querying libdisid directly http://tickets.musicbrainz.org/browse/PICARD-503.
Unfortunately, in Arch this is still an AUR package https://aur.archlinux.org/packages/python-discid/, so the dependency isn't shown when installing picard-1.3-3 https://bugs.archlinux.org/task/42587.
Build the AUR package and install python2-discid-1.1.0-2-any.pkg.tar.xz to restore disc lookups in Picard v1.3. (Installing the python-discid-1.1.0-2-any.pkg.tar.xz won't work at this time. See https://bugs.archlinux.org/task/42545)
I'm adding this topic to help others quickly Google this issue, since the relevant bug reports against picard-1.3 are already closed.
Any technology distinguishable from magic is insufficiently advanced.
- Cleon, _Foundation's Fear_
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