hi, there is already work going on to convert firefox to a multi-process architecture: https://wiki.mozilla.org/Electrolysis based on that work, in the future the browser may also have separate processes per tab.

Looking at that link and especially the Roadmap page my head spins at the sophistication, and all the people and pieces making that a massive project. i have faith that wise heads are handling it. What I can't tell is when the switch occurs. I understand that there's a lot of testing and contingencies still ahead and I have faith that it will be "ready when it's ready but not before it's ready." A tall order (readiness) given the project complexity. I can see why it's not been addressed for years, it's such a huge undertaking. I say this all in high compliment to the engineers in charge.

But regardless of whether it's next month or next year I understand that my suggestion is not worth significant investment if the big change is imminent. So I'll drop the idea and give you a "solved."

Thanks for your clear answer and everyone's great work on this.

P.S. I for one am heavily in favor of the change being user-transparent, as much as is practical. Please don't be like Microsoft and use the big change as an excuse to stuff down everyone's throat a new look and feel and clicks and keyboard shortcuts - as much as is practical. Please :) "It ain't broke" in terms of the interface! Way ain't! It's great.

I changed my mind. I think the situation is so severe that emergency action is warranted.

44 and recent versions crash and/or hang so severely - every 20 minutes for me on Win 7 Pro, with 24G of memory, new Dell desktop - that waiting for the redesign will allow far more costly amounts of damage in the meantime. (Sometimes I have to kill process for a hang, and these aren't reported. When it does crash, under half are reported; either the crash window self closes after a minute, or never appears at all. At any rate, my suggestion speaks the the hanging problem, though crashing is severe too.)

Please look at my suggestion. On the surface it seems extremely easy to accomplish.

There are other problems - windows are never restored in correct order, ever, ever, and keyboard shortcuts continue to be useless as in every past version - but there's a severe problem with instability and something desperately needs to be done.

Look if simultaneously having 3 Facebook and 2 YouTube windows open hangs a machine 24% of the time, okay, I'll deal with the limitation. But we need to know that, and even if the redesign was completed next month (is it? Or out of beta 3 years from now?), why not consider my suggestion in the meantime. Thank you.

You guys have done such awesome work. The multiple session and bookmark recovery work masterfully and truly are lifesavers on occasion. Someone deserves a Congressional Medal for both that and Control-Alt-N. FX is the greatest browser ever made. It is everything that Microsoft will never be and never "get." But it's unstable.

You are now mentioning memory issues please see

• Firefox uses too much memory or CPU resources - How to fix
• and you may also be interested in cpu Firefox uses too much memory or CPU resources - How to fix

Note you may try out the multi mode Firefox already. Firefox Developer Edition is a pre release version of Firefox. By default

• It installs as a separate additional browser.
• It has its own profile set up separately.
• The optional mult mode function is set to be on

This is the E10s feature Philipp mentioned. The Developer Edition does update every day. It is stable enough for me to use as my default browser. The E10s feature is not yet ready for Release and it us not compatible with some add-ons. Details and download from

• https://www.mozilla.org/firefox/developer/
• https://www.mozilla.org/firefox/channel/#developer

I would agree sometimes new Releases have issues, unfortunately these often necessitate additional quick releases with fixes, however generaly the Release is very stable.

If you need help with crashes start a new question. See Troubleshoot Firefox crashes (closing or quitting unexpectedly)

I suggest you wait a couple of weeks so we have time to get used to any teething troubles, but then update to what will be the current Firefox 45 We do not support outdated insecure versions and so there will be no point in asking for help with Firefox43 for instance.

If you post a new question within the next few weeks let us know by mentioning that in this thread.

I often run multiple tabs and multiple Windows without gangs and my only Windows 10 machine is either 2GB or 4GB but I have nothing like 24GB.

Oh I should mention there us now a 64 bit version of Firefox for Windows, it is not fully mainstream but in Release at last. Linux & Mac have had 64 bit Firefox for years.

I had a broken link in my last post Firefox uses too much memory or CPU resources - How to fix

Thank you for your kind concern. Memory is not the issue. CPU is the issue. THE issue.

Something needs to be done NOW to identify which webpage is sucking cycles. Not 3 years or 9 years from now when the redesign is complete and stabilized for mass use. I should be able to run 90 windows; I have frequently done just that, smoothly, painlessly, many times. However, in an inconsistently seeming fashion, from time to time, Bang - the CPU consumption goes through the roof.

I have a new i7 Dell running Windows 7 Pro. With tens of gigs of memory. Yet sometimes - there is no clear pattern - FX, even shortly after starting, with numerous windows resumed from sessionstore, is burning 13% of CPU. The number normally is 0 to 1%. I gather that 12.5% is the theoretical maximum for this box.

Thanks for suggesting Beta versions. Thanks for your hard work on the new versions. But I don't need the additional pains that come with Beta testing; just a stable FX. And knowledge of which sites suck CPU. The serious problem that developers have failed to address for many years now is to IDENTIFY WHICH WEBPAGE IS EXPLODING CPU USAGE. In the top post I have suggested a simple way to achieve this. At least look it over. The whole thing might be solved in an hour.

FYI v. 45 is nearly if not equally as bad as 44.

After going though your links, John, I did turn off hardware acceleration. Pages seem to load much more slowly (hard to tell, since ISP may be the culprit), but I have lately crashed only 11 times per day instead of 16.

P.S. My earlier post was misinterpreted. I have 24G on my box and FX uses 2, not 24. Memory usage is not the problem.

P.P.S. On every restart of FX since about version 2 or 4, the z-order of windows is scrambled. I have to reorder everything. WTF happened since the early versions to destroy that functionality? I think the sessionstore windows reload too fast for Win 7 to order them correctly. Point me to a thread to report this. I suspect that a quarter second or so delay between page reloads from sessionstore would allow the O.S. enough time to order them correctly.

I am sorry if Firefox is not living up to your expectations, but I am not sure there is anything we can do to assist if problems are only seen with 90 windows and multiple instances are open.

P.P.S. On every restart of FX since about version 2 or 4, the z-order of windows is scrambled. I have to reorder everything. WTF happened since the early versions to destroy that functionality? I think the sessionstore windows reload too fast for Win 7 to order them correctly. Point me to a thread to report this. I suspect that a quarter second or so delay between page reloads from sessionstore would allow the O.S. enough time to order them correctly.

I have a vague recollection that could be a known issue. Please start a question thread about that and with luck someone will give you a correct answer. If you post back in this thread once you have done that we can make sure the threads are cross linked.

The serious problem that developers have failed to address for many years now is to IDENTIFY WHICH WEBPAGE IS EXPLODING CPU USAGE.

If you are looking for a solution by way of a Firefox fix or feature you are in the wrong place. Make a short comment using Feedback. Or add a post to the wishlist. Of course as the person using the websites maybe you can identify such a website yourself. If CPU use is exploding the culprit should be identifiable.

• mozilla.org/about/forums
  • mozilla.org/about/forums/#wishlist
• input.mozilla.org/feedback/firefox?#moreinfo
  • Interactive viewer here

(#answer-853341} 44 and recent versions crash and/or hang so severely - every 20 minutes for me

If you get crashes we may be able to help if you share the crash IDs with us. You may be able to get some insight into the hangs using the builtin profiler or using a profiler addon, but again if the problem is with 90 windows open it is not going to be practical to sort out.