To be thorough, select "Privacy and security" in the sidebar, then click "Security" on the right side, and be sure to turn on ...
When your search engine keeps changing to Yahoo, it's most likely a virus, and you can fix it by resetting your browser. Here ...
New Edge flags suggest that Start menu searches can use your default browser and search engine, rather than Edge/Bing. Flags like msWSBLaunchNonBingDSE indicate searches could launch non-Bing engines ...