Midi export doesn't function properly
I created a quartet score and then created separate parts--Tenor, Lead, Baritone, and Bass. The parts show up correctly in Musescore, but when I try using the "export parts" feature in Musescore, the tenor and lead files are exactly the same (they both have the other's part in the file) and the baritone and bass files have no midi information. The same thing happens when I export to MP3.
I think this is a bug because this was working prior to me updating Musescore.
OS: Windows 10 (10.0), Arch.: x86_64, MuseScore version (64-bit): 188.8.131.5278, revision: e26f7c4