Just to add some more to that, to save some backtracking. Cookies are enabled, and I have tried restarting Firefox in Safe mode. Still does not work.

Bump. No response, question too hard ?

Normally, a new tab in the same window shares the same "cookie jar" as the other tabs in the window. Therefore, Google Drive should be in the same context as the other Google applications. (I'm assuming you don't block third party cookies -- Websites say cookies are blocked - Unblock them.)

Two exceptions could be (1) using container tabs, or (2) using a private tab extension.

Otherwise, yes, too hard.

Thanks for your suggestion, but yes, I have cookies enabled, and have tried clearing them etc etc. Nothing works.

I really like Firefox, but this is getting really annoying.

Aha! Finally got it to work ! Follow the instructions in https://support.mozilla.org/en-US/kb/websites-say-cookies-are-blocked-unblock-them Go right down to the final procedure to select Exceptions and set the URLs for Google Found both http://google.com and https://google.com had cookies set to "Allow 1st party only" Set that to "Allow" and it works. This was being set even though I had cleared cookies several times before.

Thanks for posting that link !

adrianjansen said

Found both http://google.com and https://google.com had cookies set to "Allow 1st party only" Set that to "Allow" and it works. This was being set even though I had cleared cookies several times before.

Great sleuthing! It's possible an add-on set those at some point in the past, as I think it would be complicated to set that particular permission yourself.