Backup file damaged

I have [[created a backup file|https://support.mozilla.org/en-US/kb/firefox-backup#w_protect-your-sensitive-data-with-a-password]] today with the latest available Firefox and switched to a new OS. Sadly, the backup file somehow seems to have gotten damaged, even if Firefox still recognizes when I'm inputting the wrong password. On Ubuntu, where I originally created the backup and where I tested it again after things weren't working out, Firefox tells me that there is an issue with the file and that I should try a different one (which I don't have). On CachyOS, which I'm currently testing out, restoring the backup never finishes and Firefox doesn't exit cleanly. In hindsight I obviously should 1) have tested the backup immediately, 2) not have wiped my laptop prematurely, and 3) have backed up the folders manually, but I haven't. Now the question: is there some way to extract the account details from the .html file? I don't care much about the rest, but restoring the accounts in some other fashion is gonna be a lot of work.