User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; fr; rv:22.214.171.124) Gecko/20070725 Firefox/126.96.36.199 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 6.0; fr; rv:188.8.131.52) Gecko/20070725 Firefox/184.108.40.206 Let's say you have a gmail account, a google analytics account and an adword account with different user name/password: currently, you cannot open them all because all tabs uses the same session. Here is Google's official explanation: "Gmail automatically signs you out of your account when it detects that you've signed out from another browser window, or when you sign in to another Gmail account from another browser window. This is done to protect your Gmail account, and to ensure the privacy of your information." I do not like that explanation and I want to open as many account as I want in my Firefox browser. Reproducible: Always Steps to Reproduce: 1. Login to a Gmail account 2. Open new tab, login to another Gmail account. 3. Try to use the first account you opened. It will sign out. Actual Results: You can only have one Gmail account open. Expected Results: I should be able to work more and be more productive by having all my Gmail accounts open.