Run Malwarebytes. Should remove it. If your browser is still stuck on the coldsearch for search engine then try this.
1. Open command prompt as Administrator.
2. Follow below command one after another
first line: RD /S /Q "%WinDir%\System32\GroupPolicyUsers"
second line: RD /S /Q "%WinDir%\System32\GroupPolicy"
third line: gpupdate /force
Restart the browser and check it should be removed.