Same here! I miss this feature and it is also a dealbreaker.
I only use Chrome for Google related Sites. Mostly, I like listening to podcasts on Youtube, while playing some games. Noticing Chrome feasts a lot of Ram, the Ram/CPU Limiter in Opera GX is super interesting for me. But i need to say, that the switch between tabs is different compared to firefox and chrome - and the type "y+tab" to search youtube is not giving... i think of uninstalling Opera GX again - even if I like this browser. It doesnt feel as fast as without the mentioned shortcuts.