What's New with Firefox 142

Lately, I’ve experienced memory leaks in Firefox that I’m too amateur to diagnose, that leads to Firefox eating 8gb of memory in some web renderer process. So when I excitedly check the changelog hoping for a summary of possible changes, I’m disappointed that there isn’t a verbose changelog for advanced users. I’m sure I could search bugzilla, but it makes me sad that the only “important” things are the headlining features.

Try about:processes and take a snapshot.

You mean more verbose than the landing page or the release notes which are also linked in the landing page: https://www.firefox.com/en-US/firefox/142.0.1/releasenotes/ ? This is a point release, even more changes are linked at the bottom of the release notes page.

I’ve had similar issues running the latest Firefox (currently 142 as per this discussion) on the latest Fedora (42). I used to be able to lock the screen and go home but I’ve recently had a couple of mornings where I’d come into work and find my system unresponsive. I use the Magic SysRq command to trigger the OOM (out-of-memory) killer as many times as required to free up enough resources that I could log in on a virtual console (Alt-Ctrl-F2). This would allow me to manually kill Firefox, freeing up about 15GB of RAM and all 16GB of the swap file.

I’ve been too busy with work to spend any time investigating the cause. At first I had been blaming the `teams-for-linux` electron app but figured that wasn’t the culprit because I close it every evening. In Firefox, `about:processes` is useful while actually using the application but I’m not really sure how best to diagnose what’s happening after the fact.

about:memory will let you generate a report that tells you what the memory is being used for.

When trying to diagnose performance or memory issues with a browser, always start with the installed and enabled extensions.

I've used firefox for 15+ years, but it starting to bug me too much. Memory issues, forced restarts that block navigation (wth!), clutter all around, having to disable sponsored crap, and random incompatibilities are starting to take a toll. I've been falling back to Edge for crying out loud.

Google AI studio sitting doing nothing (not even a chat loaded) was eating 8 GB and lots of CPU.

Some of the new ai slop features lag our firefox

Go into about:config and search for browser.ml stuff. Some of it is just for text completion, but you can also load models - transformer js, and also send stuff to chat gpt.

Yep. Can’t upvote this enough.

Next up would be looking closer at the pages you frequent. I think many people would be surprised at all the ways web apps screw up these days.

All that said, the browsers, as unfair as it may seem, should do better at handling all of the slop that web app and extension developers put out there. It’s sometimes just a whole lot easier to make the browser more bulletproof than it is to make a bajillion JavaScript/python monkeys conscientious and competent.

No they don't, please stop spreading misinformation. There was a performance regression due to the new vector search which was fixed before it even reached 1% of Firefox users in the US alone: https://news.ycombinator.com/item?id=44912974

> forced restarts that block navigation (wth!)

From what I understand, this is because the OS package manager changed some of Firefox's files in a background update (Ubuntu does this through unattended-upgrades), and Firefox's built-in updater doesn't have this problem.

These days, I'd say always start with the YouTube tabs.

Youtube is just hopelessly broken on Firefox/Linux anyways. Half the time the home page doesn't even load.

An alternate between those two endpoints would be to offer better tooling to enable both users and monkeys to identify things contributing to bad outcomes. I don't just mean devtools, either, I mean "oh, it seems this tab is taking up $foo memory because the background image is a 400MB .mp4 and ..." type thing. They went through all the trouble to put AI in the browser, so ask it :-/

What type of problems do you have? I use YouTube in Firefox on Linux almost every day and as far as I can tell it's working perfectly.

I don't go to the home page, though, only access videos via search (using !yt on Kagi) and by clicking around related videos.

I don't see any memory issues that the OP is talking about, either. Maybe uBlock is fixing it for me?

It is very likely that one single site is responsible for this. For example in my usage, Jenkins portal is leaking memory like hell, will fill up a few GBs in a a day and jack up CPU utilization to 100%.

I has hundreds of tabs at that point, so I had to find out the culprit. What I did was open a task manager and expand Fifefox process to see dozens of subprocesses. I then sorted by memory (or by cpu) to find out worst offender and killed only that single subprocess without touching others. And after doing that I've looked at the list of tabs and saw that one of them has changed to the crash report tab, with a visibly different icon. And looking at it I saw that it was originally Jenkins portal. Now I proactively close it's tabs and leaks stopped. Maybe this will help you.

Same, it started this year. Once a week or two YT just refuses to render its page completely.

I only use ff on windows. No issue. I do have premium. May be adblocking YT is broken. I have ublock turned on too, but no issue.

Or about:performance, for a less detailed but arguably nicer quick overview.

If you click on "See full release notes", there's the link "Complete list of changes for this release" at the bottom of the page on the right that points to this: https://bugzilla.mozilla.org/buglist.cgi?j_top=OR&f1=target_...

Is that what you're looking for? If you sort it by updated, I assume everything after the 27th is probably in the current release.

cool. There is also about:performance with cpu & memory for each tab / addon. Hmm, it looks like all extensions are combined in a single entry. So, maybe not per addon.