Search all open tabs in Firefox: prefix your search with "% " (percent followed by a space).
Or don't, and it'll probably be in the list of suggested results anyway.
(Unless you're using container tabs, in which case it'll only search open tabs in the current container, which is sometimes good but usually a nuisance.)
I much prefer Firefox's address bar search heuristics over Chrome's, but it definitely depends on your usage patterns. Firefox is very good at suggesting relevant things from my history, to the extent that I will gasp actually close tabs now and rely on search to rediscover them, rather than forever accumulating open tabs that I might want to get back to.
Or don't, and it'll probably be in the list of suggested results anyway.
(Unless you're using container tabs, in which case it'll only search open tabs in the current container, which is sometimes good but usually a nuisance.)
I much prefer Firefox's address bar search heuristics over Chrome's, but it definitely depends on your usage patterns. Firefox is very good at suggesting relevant things from my history, to the extent that I will gasp actually close tabs now and rely on search to rediscover them, rather than forever accumulating open tabs that I might want to get back to.