Please also update to version 32.0.3 there is a critical security issue that was addressed in this version. I do not know about the link, but it could be a corrupt cache. See if it happens in Safe Mode to make sure it is not an add on. Diagnose Firefox issues using Troubleshoot Mode and clear the cache to make sure its not the page.

Its possible to forget the site to clear the cache for just the site in about:permissions.

Still have the problem

Is it possible to block pop ups for the homepage? This may be a script running to verify that you are logged in.

• Pop-up blocker settings, exceptions and troubleshooting

The other research on this is that it may be a plugin or a cookie expiring if your homepage shows that you are logged in or not. Does changing the yahoo homepage still add the same 2-3 to take the page to load times?

Diagnose Firefox issues using Troubleshoot Mode will help determine if it is a plugin.