My default search engine changed after updating Firefox to version 98.

Why did my search engine change?

This change is happening because Mozilla was unable to secure formal permission to continue including certain search engines in Firefox. We provided an opportunity to previously-included search engines to sign an agreement and the engines that did not complete the agreement will be removed from Firefox.

Not sure why you remove the engine and then force people to install plugins or extensions. Extensions and plugins are always critical, outdated or use useless resources.

Why not just add an option directly in the GUI do add this directly without depending on others, beyond me.

I also dislike how Chrome handles it, it is restricted and tighten up because people remove everything and then they complain afterwards because there is no reset button, thankfully after lots of pressure Chrome will address this but honestly the whole thing in every Browser is miserable handled.