GRR ARG

Sometime in either this version (15) or the previous version of Thunderbird (fuck Chrome-style version numbers.. fuck them up their whatever they have), it's started to fairly frequently forget the setting for View > Sort By > Threaded in all my folders, and sometimes to also forget the customized column headers in the message list. Not all folders at once, but in some kind of rotating fashion, one at a time. Every so often, eventually, I have to keep resetting every single folder to threaded view and reapply its column headers (not at the same time, but it seems random).

Has anyone else been having this issue? I Googled it but can't seem to find any hits from anyone else having the same kind of problem.