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???

If you go to about:memory and click on "measure" you can see a bit of where the memory is going. The per-tab overhead isn't that high, but unfortunately there's quite a bit of overhead to have the browser open at all, so it looks rather silly when you have a single tab open.

There is Javascript interpreter, caches and other memory consuming things ;)

For a single tab? I wonder how much the telemetry takes up...

Cold start after updates make me think something didn't get clean properly.1.5GB for a single tab still feels like a bug rather than expected behavior.

Although I'd like to read and respond to the reply made by Emre_Ozkan, it is unfortunately [flagged] and [dead]

Quite disappointing whenever I see this type of...of censorship, would this be considered??? I am sure there are many interesting perspectives and this is not the first occurrence of burying comments and/or responses that I have observed as a longtime lurker

It's the first comment from a new account so probably caught in some kind of spam trap.

You can vouch for comments (possibly depending on level of account karma) if you click through to the comment alone.