Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there?

Issues have been previously linked to the McAfee Site Advisor extension. Try to disable it and see if the problem persists.

http://service.mcafee.com/faqdocument.aspx?id=TS100162 How to uninstall SiteAdvisor

To disable it: Type "about:addons" in the Location bar Find the extension and click on its "Disable" button

I uninstalled Mcafee. I uninstalled Mozilla and reinstalled Mozilla, same problem. I only have this problem on Mozilla and not my other web browsers!

I uninstalled Mcafee. I uninstalled Mozilla and reinstalled Mozilla, same problem. I only have this problem on Mozilla and not my other web browsers!

check this:

• see if there are updates for your graphics drive drivers

https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

• disable protected mode in the Flash plugin (Flash 11.3+ on Windows Vista and later)

https://forums.adobe.com/message/4468493#TemporaryWorkaround

• disable hardware acceleration in the Flash plugin

https://forums.adobe.com/thread/891337 See also:

• http://kb.mozillazine.org/Flash#Troubleshooting

Start your Computer in safe mode with networking. Then start Firefox. Try Safe web sites. Is the problem still there?

Starting The Computer In Safe Mode;
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