And inherently a far less ram using browser. I do 500 tabs in under 3GB. By also not implementing all the useless attack surfaces like DRM, Integrated PDF reader, WebRTC, and friends it avoids many of the exploits which make modern browsers like FF and Chrome insecure. Overall it probably balances out. Especially since PM users are likely to have JS execution disabled by default (like I do).

It's pointless to say things like "500 tabs under 3GB" without knowing what's loaded in these tabs.

Can you think of any realistic tab set that would result in Chrome or Firefox using as little memory?

I'm not the one that should prove anything here.

My point is that if you cannot create a single tab set that beats what GP mentioned in your preferred browser then his browser still uses less memory.

That said, none of this is scientific so I will leave it here.

Well, it's not Facebook, Twitter, Discord or the like. I'll to you that. It's mostly actual websites written in HTML (like HN). But even with no websites loaded if you tried to open 500 blank Chrome tabs you'd run out of RAM. That's just the nature of per-tab many process browsers.

And 500 is just my actively loaded tabs. I have another 500 suspended.

Multiprocess would have fewer libwebp bugs?