Disabling the addons is only a Diagnostic test. Some of those addons are very helpful. Right now I usually would tell you to enable one addon at a time and test. But you have given me sufficient information to diagnose.
We now need to make certain that this issue is not malware because if we troubleshoot otherwise we may be wasting our time.
I suggest you go to the
Malware Forum and run all the steps located in the
START HERE. These self-help tools will help you clean up 70% of problems on your own. If you are still having problems after doing the steps, then please post a HiJackThis Log in
THAT forum. If you are unable to run and/or post a HJT log, then post that in your initial post in the topic you create in that forum.
If you are still having problems after being given a clean bill of health from the malware expert, then please return to
THIS thread and we will pursue other options to help you solve your current problem(s).