Firefox is down at
A temporary solution has been given, it consists in deactivating one of the functions internal to the browser. Type “about:config” in the address bar then after confirming access to the settings, type “network.http.http3.enabled” in the search field. And disable this option by clicking on the icon on the right.
Relaunch the browser and it should work normally again, but eventually you will have to reactivate this option. Obviously if you had not seen any problem previously, this change of state for this variable is not necessary.
This behavior is linked to the browser’s management of the future http3 protocol that sites are gradually beginning to adopt. Mozilla would have made a modification to one of its web services that Firefox uses and which would have revealed this bug.
Update at 2:15 p.m. : Mozilla said to have found and fixed the source of the problem. A restart of the browser should suffice. More information will be given later.