I've been using LP on many different configs (Mac and Windows, Chrome and Firefox). I recently started using Kubuntu (19.10) and Firefox (72.0.1 (64-bit)). Whenever i have to save a new password, i get "ERROR: Hmm... This is taking longer than usual." and nothing saves. Only solution i found is going to the LP website, open my vault and add the new pwd manually, but this is not something i want to keep doing.
I did find people reporting similar sounding issues, and find it interesting many have no replies with a solution. Like viewtopic.php?f=12&t=352855#p1175785
I also noticed using Chrome works, so it is the Lastpass Firefox combination.
I could not find info on how to troubleshoot, so i hope someone can help or suggest how to proceed?