The ordinary Firefox Release would be slightly more stable.

However as you say it goes on for months I suspect the problem is something with your setup, or maybe even with how you use Yahoo.

Is the issue only on Yahoo content that you need to login to use.

• Do any other sites give problems ?
• Are all sites including Yahoo ok on Internet Explorer ?
• Do you get any error message ?
• Please try clearing your cookies for the Yahoo site and clear the cache or at least use the Ctrl F5 keyboard shortcut to reload the site

Please See

• Clear cookies and site data in Firefox_delete-cookies-for-a-single-site
• Firefox can't load websites but other browsers can
• Diagnose Firefox issues using Troubleshoot Mode
• Disable or remove Add-ons

• Did clearing cookies and cache help ?

Please also try in Firefox's safemode, and if that does not help then in safemode with all plugins disabled. Your extensions could be interfering as you have script and ablockers and a cookie manager.

• Does Yahoo work (not lock-up) when in safemode with all plugins disabled ?

Thanks John for the quick reply, I'll try to answer what I can now and follow your suggestion to TS the issue further. My link to Yahoo is the sign-in page, so that's the first thing I do, the lock-up happens about 10 seconds afterwards when Yahoo's homepage is displayed, before I click on anything, although if I'm quick I can get mail to open before it locks. I have not seen this happen with any other site, (the music on the Pandora tab opened first always stops when the Yahoo lock happens) or any other browser IE or Chrome. No error messages on screen or in the Event Viewer. The lock-up only happens once in the morning after the computer is booted and first time into Yahoo. The cache/cookies is set to clear every shutdown. I will try the clear for Yahoo on next start up before logging in to see if that helps. It's just annoying and other than the minute hold up everything is working so bare with me if I don't spend a lot of time on reboots until I get more time to investigate. Thanks for the help.

Firefox 44 does have a known bug. Whether it also affects Fx 45.0b I am not sure. If it does affect you it will be another complication.

It has odd effects. It is due to problems on shutdown (which may go un-noticed) then does odd things on restarting. It only affects users where some sort of sanitise happens on close down, e.g. clearing History.

That may be a red herring here ! I am making the comment just in case it needs considering once more likely causes are ruled out.