I'm not aware of any browser that implements "per-tab content processes". For example, Chrome caps the number of content processes and multiple tabs in Chrome start sharing the same content process once enough tabs are open.

Technically speaking, it's a lot easier to do a separate process per tab, and let things crash just like any other running process. If they don't stop there and try to actually manage processes by themselves according to some messed up logic, then yes, I agree with you that there's no point to e10s and probably Mozilla.

> and let things crash just like any other running process

People always say that as if crashes would be a regular thing happening every few minutes. I don't experience browser crashes for days, so I find it kind of odd that such a relatively rare failure case is considered a good justification for using a process per tab.

I stopped using Chrome a couple of years ago because of multiple crashes per day. The browser itself didn't crash, but individual tabs did. Or else Chrome tabs failed to load (giving just a pale blue background) presumably because it had run out of RAM.

I used OneTab for a while, to reduce memory use, but still found Firefox more efficient and more stable with hundreds of tabs, mainly because the vast majority weren't actually loaded until I needed them.

It's not hard to crash Firefox -- just keep loading an infinite page of gifs etc. But once you know that, you don't do it.

Under normal working conditions, I agree: none of the main browsers crashes often enough for it to be a problem.