@GlennD: It's off-topic for this thread but that's not my experience; I do delete most cookies when closing my browser, but Lastpass is whitelisted. That workaround did used to work, but no longer - I now get prompted once again to accept Permissions in every new browser session.
I'm having the very same problem. I use Firefox 84.0.2, which FireFox says is up to date.
The LastPass icon in the top RH corner of my browser is showing yellow/orange. When I click on it, I get the little safe deposit box/safe icon whirring over and over, but never stopping. My passwords on websites don't get filled. There is no problem with my internet connection.
RachelO mentioned that LP are working on this problem, but that was in December 2020, I recall, and it's still happening on 14th January 2021.
Not just Firefox. Also a problem for me via Chrome.
I've been a LastPass Premium user for several years. Recently when I attempt to login via the browser (Chrome, Firefox) toolbar icon, I see a spinning vault door image which never resolves to a login. Restarting the browser doesn't help, and switching to another browser results in the same failure. The only solution is to try to login at lastpass.com. This turns the icon yellow, but the vault is open! Lately I have also experienced this: I successfully login via the toolbar icon, it turns red (Firefox), I open the vault in it's own tab, I work for 1-2 minutes on something else and then notice the icon is not red, and the vault tab shows I'm logged out. But I didn't do that. And it repeats.
I created a support case #14659903. Got this response 1/11/21:
"1. Kill all sessions
2. Clear local cache
3. Clear browser cache from last hours at least, with the cookies and history.
4. Log out from the extension. Closing all the LastPass windows open.
5. Reopen a brand new web browser window, then log back in from the extension, and reopen the vault from there too.
6. Uninstall and reinstall the latest extension from https://lastpass.com/misc_download2.php"
I did all six steps with both Chrome and Firefox. That day it solved my problems. The next day the problems returned. I responded to support, and got this 1/12/21:
"I´ve to tell you, this is a known issue where my Development team has been working on it for a really good while. If after the previous troubleshooting steps you got no changes. The last step is trying another web browser. "
And then this 1/13/20:
"My most humble apology for this painful hassle. About FF is a known defect where my Development team has been working on it for a good while. About this new incident under Chrome, I´m waiting for my support team can provide me a better expectation. Once I´ve it handy, I´ll let you know. "
I'm afraid the fact that WireCutter no longer recommends LastPass (because parent company LogMeIn was acquired by private-equity firms) was predictive of this product's problems.
So now I believe there is a 7th step not mentioned by support, above.
7. Switch to another password manager.
You can export LastPass data to a CSV file, and import it to other managers.
Thanks a lot, Edhome.
This is quite a hassle, and there's no guarantee that it will produce a lasting solution.
I'll be looking for a reliable free password manager. Thanks for the tip about exporting the LastPass data to a CSV file.
So something a bit new on this. I had posted a while back that it seemed like it happened when the firefox extension "timed out".
This time I logged into lastpass, and about 15 or 20seconds later I got a popup message something like "lastpass has timed out, please login again to use it" (not exact words), and the icon was orange and I could NOT log in again, it put up the rotating icon forever.
I had to disable/enable the extension to login again, and its OK - for now.
Lastpass seems to work in other browsers (Edge, Chrome), I have not seen this issue in either.
I tried to drop Lastpass, tried a couple of others and deleted them -- just didn't work as well as LastPass, ignoring the current issue.
Other Browsers don't do a nice pinned left-sidebar of bookmarks, which I REALLY like. So I am waiting!!