Google two-step verification
I have recently enabled two-step verification in Google. But whenever I try to login to Gmail, which is often since I delete cookies after session is closed, the Google website immediately outputs a message about me taking too long to answer the smartphone confirmation message. I restarted Firefox without addons and I could login.
Then I disabled one by one my Firefox addons and found that Smart Referer was the cause of the Google misfunction. I found that https://www.discourse.net/2019/03/smart-referer-firefox-extension-blocks-google-two-factor-authentication/ has had the same problem.
After using the network console for the first time in my life, I came to the conclusion that
Source:
accounts.google.com
Destination:content.googleapis.com
in the whitelist solves the problem. Please review it and add it to your whitelist.
Thanks for the addon.