Try this :- https://support.mozilla.org/en-US/kb/signing-in-using-persona?esab=a&s=We+are+sorry%2C+but+currently+your+browser+is+not+supported+in+persona&r=1&as=s This may help you . Please reply and tell us whether this helped you!

This can be caused by corrupted cookies or cookies that are blocked (check the permissions on the about:permissions page). Clear the cache and cookies only from websites that cause problems. "Clear the Cache": *Firefox/Tools > Options > Advanced > Network > Cached Web Content: "Clear Now" "Remove Cookies" from sites causing problems: *Firefox/Tools > Options > Privacy > Cookies: "Show Cookies" You can inspect and manage the permissions for the domain in the currently selected tab via these steps: *Click the "Site Identity Button" (globe/padlock) on the location bar *Click "More Information" to open "Tools > Page Info" with the Security tab selected *Go to the Permissions tab (Tools > Page Info > Permissions) to check the permissions for the domain in the currently selected tab Start Firefox in <u>[[Safe Mode|Safe Mode]]</u> to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance). *Do NOT click the Reset button on the Safe Mode start window. *https://support.mozilla.org/kb/Safe+Mode *https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes