I would remove all search engines except for Wikipedia and Chambers dictionary, and go to https://mojeek.com and add it to Firefox and make it the default search engine. If you don't get the results you want, it offers other search engines such as Brave. I don't use any of the alternatives that Mojeek offer, just Brave.
Ugh the issue still exists , workaround i've been doing is not shutting down my laptop which i don't really mind but whenever i shutdown / restart and then open browser it takes about 3-5 mins to be properly usable again.
Btw all other things work great its just Firefox that's slow
For a few months now, I've been experiencing something similar in Debian 12. When I launch Firefox, sometimes (around 10% of the time maybe?), nothing happens. I haven't checked if it does eventually popup after a few minutes however, so it may not be the same issue. Anyway, this is how I "fix" it:
Find the process ID by running on terminal: ps -ef | grep firefox. There should be a single entry pointing to the executable, something like "/usr/bin/firefox" or similar. Take note of the second column.
Kill the process with kill <process_id>. Sometimes I need to force it, sending a signal: kill -s SIGKILL <process_id>. This goes without saying... make sure you enter the correct process id!
Re-launch Firefox, everything goes back to normal.
I wonder if by doing this I'm somehow making things worse, but I still don't even know what caused it in the first place. Other than this mild annoyance, Firefox works great for me so it seems to be safe to do so.
Again, this happens only sometimes to me, so this may not actually be the same issue.