reset chrome - turns off all extensions.

If you have any issues with chrome, especially anything related to malware, ads, search bar going to yahoo instead of google, etc Try this. This will disable all extensions among other things. If chrome is reset and the problem is resolved then you know the issue is related to an extension. 

Hit the three dots

settings

reset settings bottom left

restore settings

Reset settings (good idea to UN-check chrome reporting but not important)