Ubuntu 21.10 - Thunderbird 91.x.x drops (movemail) mbox support!

I just upgraded from Ubuntu 21.04 to Ubuntu 21.10.

Baring a few glitches here and there, it's now running ok.

However, I just discovered that Thunderbird 91.x.x removed movemail support! That means that I've lost support for my /var/mail/* mboxes!

Other than installing another mail program, like possibly Evolution, is there any way to get to my mboxes again?

source: https://bugzilla.mozilla.org/show_bug.cgi?id=1625741

excerpt from comment 35...

Anyway, for whoever wants to know a slightly kludgy but likely "good enough" workaround, do this:

• context-click on the "Local Folders" and find the "Local Directory" address
• close thunderbird (maybe be paranoid and pgrep to ensure you don't have any persistent subprocess still running)
• then create a symlink ln -s /var/mail/[SPOOL_FILE_NAME] /path/to/the/Local-Directory/address/you/found/above/Inbox (obviously ensure there isn't already an Inbox subfolder there, or otherwise create a differently named subfolder-symlink)

When I opened thunderbird it indexed it OK and after exiting and reopening thunderbird several times the symlink has stayed in place without problem.