Hi, could you provide a few more details --

Which site isn't working? For example, Google, Bing, DuckDuckGo.

Is the problem presented as an error message, blank page, etc.?

If you go to the search site's home page and submit your search there, does it work better than using Firefox's address bar?

If it's DuckDuckGo and you use the MetaMask extension, you need to change MetaMask settings. See:

https://github.com/MetaMask/metamask-extension/issues/31094

The authors have a version 12.12.1 update as you can see at https://addons.mozilla.org/firefox/addon/ether-metamask/versions/