I suspect a lot of it is just a premptive cache. My daily runner laptop is a 2009 Core 2 Duo with 4GB of RAM and Firefox only uses about 1.5GB max when there is about 20 tabs open. It tries to fit in with whatever system it is running on.

Back in 2006 I remember using Firefox on a WinXP system with only 128MB of RAM, while the start up time was dreadful, once it had finally mapped out the memory/swapped all the right parts to the HDD it was surprisingly snappy. I would guess it is still doing something like that now only it doesn't have to swap it out anywhere.

Truly intriguing! A core2duo+4GB RAM in 2026?!?!!!

Can you elaborate on your experience? I can't imagine 20tabs being smooth on 8GB with the modern "web" being whst it is today, let alone 4GB! Unless there is only text files and plain HTML in those 20 tabs???