Yes, although it might not happen immediately. That's exactly what this fix helps with. And see https://bugzilla.mozilla.org/show_bug.cgi?id=668809 for more about this.

But then the Ctrl+Shift+T feature to reopen closed tabs wouldn't work so well. Try it, you can reopen closed tabs as far back as you like; it's pretty awesome and has saved me more than once.

It doesn't work in Private Mode (for good reason); I wonder if browsing in private mode consumes less memory?

I like that feature and use it. But it can be separated from the memory caching. Back button speed is nice too, but I could do without it.

There are a few options here ... keep the last one in memory, the last few in the disk cache, etc. Right now it appears to keep everything you've ever visited in RAM, which is clearly wrong.

Hmmm... how about using Private Mode through a proxy to keep your history?

I believe that there are also some information-theoretical limits on the efficiency of garbage collection and memory allocation. Don't quote me on that, though.