Question:yeah....a thousand people have this same exact question, but the answers are always for internet explorer!
Answers:
So the answer will be exactly the same, i am not habitated to use Mozilla Firebox ,but i can give some basic, common causes:~
It's for your web page is not loading properly. The cause is multi-dimentional. It may be because of slow internet connection,Problem with the server of Mail beta with your 'webmaster', active java scriptings,applets not enabled, corrupted browser cache,windows firewall or any personal anti-virus firewall (being too tight to communicate),lack of adequate windows resources or physical memory RAM of your system,infected system,problem with the .dll files of your browser or invalid or deleted or corrupted resistry of your mail installation.
The problem can be from other party also but in that case it has to be temporary
contact Yahoo! feedback support if you wish
You can fill out a feedback form online:
http://help.yahoo.com/fast/help/us/mail/...
You can also E-Mail the Yahoo! Customer Care:
cc-advoc@yahoo-inc
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