1. disable all add ons. if the problem is still there you have a browser hijack issue.

  2. Run a Malwarebytes scan to see if that finds the problem.

  3. You should dump a most of those add ons, you have several items there that do the same job and avast covers almost all of them.

Adblock Plus
Avast Online Security
Colorful Tabs
Do Not Track Me remove
Dr. Web remove
Ghostery remove
McAfee Site Advisor remove
Track Me Not remove
Webutation remove
WOT remove

The other tool to use to remove this problem would be this >>> ADWCleaner