alt Hacker NewsmacOS will pop up a window that says the system has run out of application memory, asking you to quit applications. I have a friend with, I believe a base M3 Air, who runs into this constantly with nothing but Firefox open.
(Been trying to get them to switch to Safari, but they prefer the Firefox name. I don't think there's anything wrong with Firefox other than it being less native.)
Does Safari use less RAM because it shares some parts with the rest of the OS? (e.g. in the same way Edge probably uses a bit less because half of its components are already idling on the OS)