Many site issues can be caused by corrupt cookies or cache.

Warning ! ! This will log you out of sites you're logged in to. You may also lose any settings for that website.

• Delete cookies to remove the information websites have stored on your computer {web link}

• How to clear the Firefox cache {web link}

If there is still a problem, Start Firefox in Safe Mode {web link}
by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh).
Did this help?

While you are in safe mode;

Try disabling graphics hardware acceleration in Firefox. Since this feature was added to Firefox it has gradually improved but there are still a few glitches.

How to disable Hardware Acceleration {web link}

Hi jones jerrett, I'm not sure which bar you are using. Is it one of Firefox's built-in bars like:

• the address bar, where the URL of the current page is displayed
• the optional shorter search bar for the main toolbar
• the search box in the Firefox Home or new tab page
• the search box in a page on the Google site
• something else?

I am referring to the Google search bar.

I am referring to the Google search bar.

Okay, so I think that means the one I've bolded here:

• the address bar, where the URL of the current page is displayed
• the optional shorter search bar for the main toolbar
• the search box in the Firefox Home or new tab page
• the search box in a page on the Google site
• something else?

Is the problem only with the mouse? In other words, if you type in the Google search box on their site and press the down arrow to highlight a selection, and then press Enter to submit that as your search query, does that work?

The question is worded slightly differently here :

https://support.mozilla.org/en-US/questions/1291909