This is strange. In my 90.0.1 64 bit works great. Are you use some add on like "User Agent Switch". This extensions can give the impression at websites that you using a different web browser ( eg. Opera, Safari etc ) Follow [https://www.whatismybrowser.com/detect/what-is-my-user-agent this ]site and make sure that browser information read correctly from websites Maybe another add on cause this issue. Try to disable some of them and connect again Clear [https://support.mozilla.org/en-US/kb/how-clear-firefox-cache cache ]sometimes helps