Is it just being rubbish for me?
I use Firefox on Win10, no problems until yesterday. Yahoo email is my homepage. It loads to the extent I can see everything in my inbox, but nothing responds to clicks, i.e. can't open mails, delete, load the basic version etc etc. Main visible evidence is the tool icons (delete, reply etc) not loading, and the page load icon remains as the revolving blue circle.
For a while yesterday it seemed to sort itself out, but misbehaving again today. Emails are accesssible via my Windows phone.