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Firefox Quantum very slow

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I updated to Quantum two days ago and I find it is very slow doing everything - typing in search box, scrolling, etc., even just closing the browser. I had no problems with previous version.

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hi diegodad, one more thing that i have just noticed when looking at your system details - can you please test if the following steps can fix the performance issue you're seeing in firefox 57?: enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named accessibility.force_disabled. double-click it, change its value to 1 and restart firefox once.

then please let us know how this goes?

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All Replies (11)

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Phillip's suggestion did work for me on my computer running Windows 7...changing accessibility.force_disabled to 1. It vastly improved the speed.

On my second computer running Windows 10...which was VERY slow when Firefox Quantum was first downloaded...on the second day the speed to load Firefox and switch between tabs was vastly increased without me changing ANYTHING. Go figure.

Bravedog, your suggestion of checking the box in privacy & security IS a quicker (and probably safer) way to make the change that Phillip provided. I hope Phillip's (& Bravedog's) change helps everyone that is experiencing an excruciatingly slow browser after Firebox Quantum installation!!!

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iv been noticing that Firefox Quantum actually uses more RAM then its Predecessors it has a much larger process tree and it continues expanding with the number of tabs you have open i have 3 tabs open and Firefox Quantum is using 6 processes requiring roughly 1.1GB of RAM compared to its predecessor that used in the range of 250-500MB of RAM

also if that isn't bad enough the update made many addons stop working and what pissed me off the most is that i had my options set to "Check for updates but let you choose to install them" but it just automatically updated my browser anyways when i started firefox a few days ago...

i had a great version of firefox before this BS it was one of the older builds i haven't updated my version of firefox since... good god i cant remember what version it was... well if the random Automatic updated when i had "Check for updates but let you choose to install them" enabled didn't piss me off enough its sure doing it now

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As noted above, disallowing accessabilty access fixed problems for 57. Today Firefox upgraded to 57.0.1 and all problems are back. https://sourceforge.net/speedtest/ shows upload and DL spedds are decreased aboput 20%, but the real kickers are latency which increases about 10 to 100fold, from 16ms 223 and then 1236ms, and packet loss consistently at 4 to 5%. After left open a while the firefox processes use up 100% of disk resources and whole computer becomes unuseable. Quitting and restarting firefox improve this but even at fresh restart, speedtest shows these awful latency and packet loss results immediately. Quitting firefox and same speedtest w Chrome I get lateny26ms, packet loss 0%, DL and UL about 20% faster. I am reposting this on a few similar threads.

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hi bravedog, reposting something at the end of solved threads won't give the issue the proper attenion - please open a new question for this problem or even file a bug report at https://bugzilla.mozilla.org/ for better results. thank you!

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This was not helpful for me. Whenever I go to do anything say launch steam or even use task manager or hit my Windows key, my system slows down to pretty much a crawl and it can't do anything until I am unable to close out Firefox. It also uses a lot of ram sometimes hitting almost 7-10 gigs and i have 16. Here is a screenshot of my task manager and what apps I have open.

My system configuration is as follows.......

Asus M5A97 LE R2.0 socket AM3+

Amd FX 8350

16 gig DDR3 1866

240 GB SSD

Windows 10 HP 64 bit

EVGA GTX 1060 6GB

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I have tried every solution listed in this post. None of them have worked. Firefox Quantum is still slow. I do not know what else to do. At this point I'm ready to just use Chrome even though I hate it just so I can do what I have to do without waiting for my browser. Anybody else have anything else to try?

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bluemyou said

I have tried every solution listed in this post. None of them have worked. Firefox Quantum is still slow. I do not know what else to do. At this point I'm ready to just use Chrome even though I hate it just so I can do what I have to do without waiting for my browser. Anybody else have anything else to try?


Why hating Chrome ? It has always been better and will always be, especially if you use many google services.

I spent too much of my time to give a chance to Firefox, even Opera is a lot better.

I hate people doing Firefox even more after reading all the bullshit that they said about how fast it is ! RIDICULOUS !

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tmbstne284

You must have some huge web pages open. My task manager shows a total of 1734 Mb used for 7 sub-processes with three tabs open and 9 add ons.

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I have the latest updates to quantum and chrome, running on an updated windows 10 system.

I tried the accessibility workaround. Doesn't help.

I tried refresh. Doesn't help.

I tried a complete clean uninstall, delete Mozilla files everywhere on my system, reinstall. Doesn't help.

The problem seems to show up most often when I run both firefox and chrome at the same time. firefox slows both browsers to a crawl.

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buythiscomputer said

bluemyou said
I have tried every solution listed in this post. None of them have worked. Firefox Quantum is still slow. I do not know what else to do. At this point I'm ready to just use Chrome even though I hate it just so I can do what I have to do without waiting for my browser. Anybody else have anything else to try?


Why hating Chrome ? It has always been better and will always be, especially if you use many google services.

I spent too much of my time to give a chance to Firefox, even Opera is a lot better.

I hate people doing Firefox even more after reading all the bullshit that they said about how fast it is ! RIDICULOUS !


Why hating Firefox? It has always been a stable and safe browser. Maybe not the best in all areas, but still excellent. It's just this latest version that is screwed up. Hopefully they will fix it soon.

Chrome is a pretty good browser, but it's not totally trustworthy. Just look at it's creator: a company that cashes in on your personal information.

Proof: I was using Chrome "incognito tabs" to do Christmas shopping this year so that my gift searches and purchases wouldn't pop up as ads, but a couple days later my searches as ads were all over the place! My wife found out what I bought for her due to Chrome! Thanks Google jerks!

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bobznkazoo said

buythiscomputer said
bluemyou said
I have tried every solution listed in this post. None of them have worked. Firefox Quantum is still slow. I do not know what else to do. At this point I'm ready to just use Chrome even though I hate it just so I can do what I have to do without waiting for my browser. Anybody else have anything else to try?


Why hating Chrome ? It has always been better and will always be, especially if you use many google services.

I spent too much of my time to give a chance to Firefox, even Opera is a lot better.

I hate people doing Firefox even more after reading all the bullshit that they said about how fast it is ! RIDICULOUS !


Why hating Firefox? It has always been a stable and safe browser. Maybe not the best in all areas, but still excellent. It's just this latest version that is screwed up. Hopefully they will fix it soon.

Chrome is a pretty good browser, but it's not totally trustworthy. Just look at it's creator: a company that cashes in on your personal information.

Proof: I was using Chrome "incognito tabs" to do Christmas shopping this year so that my gift searches and purchases wouldn't pop up as ads, but a couple days later my searches as ads were all over the place! My wife found out what I bought for her due to Chrome! Thanks Google jerks!


Only Firefox last version is bad ? So wrong. So many problems, so many times during the last 10 years.

Chrome never had 10% of Firefox problems, it's a fact, and it has always been faster, it's one more fact.

If you need privacy it's easy, just do not browse Internet.

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