How to Set Up and Use a Firefox Proxy for Better Privacy? or Is a Firefox Proxy the Best Way to Brows

Proxies can be finicky, especially in Firefox. Have you checked if the proxy server is even online? Tools like ProxyChecker or Hidemy.name can help verify.

Also, clear your cache and cookies. Sometimes old data messes with the connection.

And yeah, extensions can clash. Try running Firefox in Safe Mode (hold Shift while opening) to rule that out.