There are problems with Yahoo Mail using Firefox but it does work when I use Chrome or my Android phone. I can only read e-mails. Cannot reply, delete, move emails. My Contacts / Address Book is empty. Most of the settings are missing. Only about 30 e-mails from the last 3 days are available. Older ones are greyed out. This happens on a Windows 11 All-in-One desktop but Yahoo Mail works on Firefox on a Windows 10 tower computer. Need more details?