Your suggestion worked and thank you very much for the same.

BRILLIANT!

had the same problem,I block all tracking but have now unblocked yahoo and compose/reply seems to be ok. had it blocked for a few weeks so don't understand why it should give problems now.

many thanks for a quick, simple,easily resolved solution for a non tech person.

Thank you very much philipp, I had the same problem after upgraded to new Yahoo Email and now problem solved after your Start Firefox in Safe Mode tip. Thanks again for sharing.

I have this same problem with the new yahoo mail. There is no sigh out or log off option in Firefox for the new Yahoo mail. However, there is this option in IE. I have multiple email accounts. Currently, the only way that I can get to different accounts if I am using Firefox, is to close the browser completely, then open it again and sign in to a different email account. However, in IE, I can simply sign out of the account (while leaving IE open) and then login to a new email account.

Please fix Firefox

I can log out of Yahoo Mail using FIrefox. Took a while for me to find the sign out option though: It is "hidden" on the top right when I hover over my "Hi, Rhonda" next to the gear and the house. I wish they would stop hiding things. LOL

Thanks for your reply, Rhonda. However, this did not work for me. I hovered over both the "hi" statement and the gear next to it. Neither action brought up the logout option.

I can sign out now. I am using the Firefox Disconnect add-on. If I unblock Yahoo analytic, then I do see the sign out feature in Firefox. It is interesting to me that I could sign out using the former Yahoo email if the Yahoo analytic was blocked.

I am having the same problem in Google Chrome. I can't compose or reply to emails while I am able to do these actions in Internet Explorer. Any suggestions?

Found problem through:

https://support.mozilla.org/en-US/kb/troubleshoot-extensions-themes-to-fix-problems

I 1st looked at: https://support.mozilla.org/en-US/questions/947605?esab=a&s=yahoo+mail+can%27t+compose+new+mail&r=0&as=s

and part way down the page it suggested Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems

which is the upper website noted.

My problem is with Chrome, not Firefox.