Firefox painfully slow

[squirm]

Anyone know why Firefox has been extremely slow for the past several months? I'm really contemplating moving to Chrome, I like FF cause of the add ons, I can block Adobe Flash, etc, but tonight was the last straw, trying to fill out online forms it was brutal. Switched over to Chrome.

[Ervin]

It's probably a bad add-on (or rarely a corrupt profile). Disable all add-ons and then re-enable them one at a time, to find the culprit.

[azurekep]

^ What he said.

If you have a lot of extensions, probably best to start FF in Safe Mode first. That temporarily takes all extensions off. Go to Help menu, select Troubleshooting Information and select Try Safe Mode.

If that doesn't work, create a new profile. In your address bar, type "about:profiles" and enter. Select Create a New Profile. If the new profile is trouble-free, you can delete the original profile.

[livesoft]

I switch among browsers routinely and often have 3 different ones open at the same time. If Firefox is slow, then clear the history, clear everything, update to latest version, etc.

Also stop Firefox and let it clear things as it exits. Then reboot your computer, too.

Anyways, I haven't noticed any Firefox slowdowns. Maybe all the sites you visit have lots of ads served up? Use an AdBlocker and see what happens, too.

[delamer]

Also have not had any significant problems with Firefox.

[stan1]

Make sure your hard drive has free space.

Also if you only have 4MB of RAM it may be time to add more.

[jebmke]

I was having problems with Firefox late last year. But I had been using the same profile that I had migrated from XP -> Vista -> W7 -> W10.

I did a Firefox refresh and that cleared things up.

https://support.mozilla.org/en-US/kb/re ... d-settings

[whodidntante]

Make sure your hard drive has free space.

Also if you only have 4MB of RAM it may be time to add more.

Yes, Windows 95 really needs at least 8 MB.

[PFInterest]

Make sure your hard drive has free space.

Also if you only have 4MB of RAM it may be time to add more.

Yes, Windows 95 really needs at least 8 MB.

Ha!

Also yes this is a system problem, not a Firefox problem.

[runner3081]

I have been having the issues. I only have two add on, ad blocker and Lastpass. Slowness and multiple crashes per day. Have tried everything and may be changing to Chrome as well.

Tried Edge for a few days, it is garbage.

[mouses]

I'm using Firefox and Chrome. No slowness with Firefox, but Chrome sinks into the dust every once and awhile. Both have AdBlock.

[boglerdude]

After a couple years, just upgraded FF to 53. The memory use is better contained to around 1GB of RAM, but CPU use is way up. Chrome seems to use less CPU. . .but I need some of the FF addons. Maybe it's that FF uses flash and Chrome HTML5

[iamlucky13]

Anyways, I haven't noticed any Firefox slowdowns. Maybe all the sites you visit have lots of ads served up? Use an AdBlocker and see what happens, too.

Are you using Firefox's included PDF viewer, or did you figure out a convenient work-around to their dropping plug-in support?

I've had terrible experiences with the Firefox PDF viewer on large documents. When they're in the several MB range, it freezes the whole browser for several minutes while they load. And just to be ridiculous, if I skip back and forth between sections of documents, such as going back to a table of contents, I have to wait several seconds while pages re-render.

Other than that, no general issues like the OP is describing.

[KSOC]

Ever run CCleaner? I've used it in the past with older PC's, clears out the bits & pieces, cobwebs & registry issues.

[livesoft]

Anyways, I haven't noticed any Firefox slowdowns. Maybe all the sites you visit have lots of ads served up? Use an AdBlocker and see what happens, too.

Are you using Firefox's included PDF viewer, or did you figure out a convenient work-around to their dropping plug-in support?

No. I use either Mac Preview or Adobe Acrobat.

[Blueskies123]

You do not say what kind of computer you have. If it is a 64 bit computer you can download the new 64 bit Firefox. You have to look for it on their website. They make it hard to find. I downloaded it yesterday and everything works faster.

As mentioned you might want to do the refresh first.

[iamlucky13]

Are you using Firefox's included PDF viewer, or did you figure out a convenient work-around to their dropping plug-in support?

No. I use either Mac Preview or Adobe Acrobat.

Interesting. Are you on Firefox 53?

I know Firefox added the built-in viewer quite a while ago, but I switched it back to using Acrobat. With one of the recent updates, Firefox disabled it completely, and would not let me switch back.

Interestingly, today I checked again and actually was permitted to select Acrobat reader for handling PDF's, but it seems to only be loading them in an independent Reader instance, not using the browser plugin.

Oh well. It's probably time I give the browser options another audit again and move away from Firefox.

[Fletch]

Old mid-2009 MacBook Pro here running El Capitan. Latest Safari update plus extensions Wipr, 1Password, Pocket. Fast and reliable. I periodically try Firefox and Chrome but always come back to Safari. I've also tried several adbock extensions, Wipr seems to do the best job on blocking. I use PDF Expert for my viewer - excellent but not free . My two cents.

[AlwaysBeClimbing]

Ditched Firefox for the same reason a couple months back(and it was a real memory hog). Tried Opera and very satisfied with performance. No need for 3rd party ad-blocker(it's built in). Recently also started blocking all cookies and just whitelisted sites that need them(surprisingly very few, I use a dedicated computer for financial websites and allow cookies there). Blocking first party cookies was more for privacy, not sure if it helps(or hurts) performance.

[DetroitRick]

Yes, I have this issue crop up every so often. On the bright side, these are almost always quick and easy to fix. So, I'll first check another browser and my own connection speed to help isolate the issue to Firefox. Then, clearing cookies typically fixes it for me. Even though I use Ghostery to reduce the issue in the first place.

I've also done a "refresh" when, earlier in the year, I was plagued by both slow speed in general, and a variety of problems on a few websites (Schwab, for example, where menus on some functions didn't work correctly). The refresh totally fixed my issues.

Restarting in Safe Mode is a very quick and easy way to see if your add-ons are at fault. Very possible cause, although that has never been MY root problem.

If you want to get fancy, Firefox has some built-in diagnostics that you might find useful in tracing a slowness issue. You just type these each in your location bar (where you type web addresses) within Firefox. They will help you see what is going on.
about:performance
about:healthreport
about:support
In addition to a wealth of diagnostic info, the about:support command will give you quick buttons to use (upper right side) to try Safe Mode, and even to do a Refresh if you need to go that far.

[Doom&Gloom]

You do not say what kind of computer you have. If it is a 64 bit computer you can download the new 64 bit Firefox. You have to look for it on their website. They make it hard to find. I downloaded it yesterday and everything works faster.

As mentioned you might want to do the refresh first.

I'm not the OP, but I wanted to thank you for this post. I downloaded it last night; I also had to uninstall the 32-bit version as my PC kept defaulting back to it. I only use FF for a few specific sites, but so far this new version does seem a bit peppier.

[midareff]

Also have not had any significant problems with Firefox.

or any problems actually

[squirm]

Hi guys,I will try your suggestions when I get a chance later this week and will report back. Thanks!

[boglerdude]

Firefox 53 is limiting itself to 1GB RAM usage, can I allow it/force it to use more? Old version of FF ate RAM but that kept the CPU use down and things fast (until it starting using the page file, then had to restart it)

[earlyout]

^ What he said.

If you have a lot of extensions, probably best to start FF in Safe Mode first. That temporarily takes all extensions off. Go to Help menu, select Troubleshooting Information and select Try Safe Mode.

If that doesn't work, create a new profile. In your address bar, type "about:profiles" and enter. Select Create a New Profile. If the new profile is trouble-free, you can delete the original profile.

I created a new profile in this manner and it greatly improved Firefox behavior. Now, how do I get my bookmarks back?

[azurekep]

^ What he said.

If you have a lot of extensions, probably best to start FF in Safe Mode first. That temporarily takes all extensions off. Go to Help menu, select Troubleshooting Information and select Try Safe Mode.

If that doesn't work, create a new profile. In your address bar, type "about:profiles" and enter. Select Create a New Profile. If the new profile is trouble-free, you can delete the original profile.

I created a new profile in this manner and it greatly improved Firefox behavior. Now, how do I get my bookmarks back?

Open Firefox into the old profile. Select the Bookmarks menu. Select Show All Bookmarks. Go to Import and Backup. Select "Export Bookmarks to HTML". Save the bookmark file to your desktop for easy retrieval. Close Firefox.

Re-open Firefox, this time using the new profile. Select the Bookmarks menu. Select Show All Bookmarks. Go to Import and Backup. Select "Import Bookmarks from HTML" This is where you import the bookmarks file you saved to the desktop.

Hope this helps.

[earlyout]

I closed Firefox and restarted but there was no option to revert to old profile. How do I get to the old profile?

[LadyGeek]

Leading question: Do you have the LastPass extension installed? I'm thinking "Yes". Dump LastPass, they broke compatibility with FireFox.

See my post here: Re: What to do with all these passwords ?

For the past week or so, Firefox was noticeably slower to respond. Not just in page load times, but switching between tabs and filling in my login entries - which are done by LastPass.

A few days ago, Firefox came to a screeching halt. For example, clicking to switch a tab resulted in many seconds of delay. Was this malware? I'm on Linux, but did what I could to check running processes - nothing found.

Chrome also seemed to be a bit slower. Is it my ISP? Nope, ping times are reasonable. Out of desperation, I disabled LastPass and all my speed problems disappeared.

A google search shows that LastPass has broken compatibility with FireFox. A lot of users also dislike the new UI. The LastPass support forum has a number of complaints and one star reviews are now appearing on the Firefox add-on site.

LastPass is unceremoniously dumped into the bit bucket. The passwords have been exported into a .csv file stored in an encrypted TrueCrypt volume.

I've been using KeePass Password Safe as my main password and data vault. LastPass was only used for online login info - I never fully trusted it.

KeePass is now front and center for online access. I've installed KeeFox :: Add-ons for Firefox, which is working just fine. It's not quite as convenient as a built-in browser app, but it does what I need.

Update: I revised my post just as runner3081 was posting below.

[runner3081]

Leading question: Do you have the LastPass extension installed? I'm thinking "Yes". Dump LastPass, they broke compatibility with FireFox.

See my post here: Re: What to do with all these passwords ?

Yes, unfortunately I have discovered that. LP kills Firefox performance.

[LadyGeek]

I closed Firefox and restarted but there was no option to revert to old profile. How do I get to the old profile?

Profiles are stored in a directory tree (folder). You backup and restore profiles by copying them to a different folder.

The basics: Profiles - Where Firefox stores your bookmarks, passwords and other user data

Also: Back up and restore information in Firefox profiles

[azurekep]

I closed Firefox and restarted but there was no option to revert to old profile. How do I get to the old profile?

Open Firefox and type about:profiles in the address bar. That should list both profiles and allow you to switch between them.

Using the (normally hidden) Profile Manager used to be much more of a pain, but "about:profiles" is the newer and much easier (!) way of working with profiles.

Report back if that doesn't work, since I haven't used multiple profiles since the've added the "about:profiles" feature. But it should work.

[LadyGeek]

^^^ Thanks! I wasn't aware of that new feature and have been using the Profile Manager until now. The "Launch profile in new browser" button does what it says. You can have more than one Firefox open, each with a different profile. Once you have that going, it's straight-forward to export bookmarks from one profile, import to another.

[earlyout]

I closed Firefox and restarted but there was no option to revert to old profile. How do I get to the old profile?

Open Firefox and type about:profiles in the address bar. That should list both profiles and allow you to switch between them.

Using the (normally hidden) Profile Manager used to be much more of a pain, but "about:profiles" is the newer and much easier (!) way of working with profiles.

Report back if that doesn't work, since I haven't used multiple profiles since the've added the "about:profiles" feature. But it should work.

That works very well. Thanks for your help.

[jacksprat]

Why not use the built in browser capabilities.. ??

Under Tools, choose 'web developer', then either the 'performance' tab or 'network' tab to begin recording/showing what's causing the issue.

Usually it's a slow script or stylesheet that is slowing FF down.. If it's a script, you can disable it from firing, but which may break the site functionality though.

Also you can then disable addons and re-test performance/network.

Of course if there's a problem upstream, everything will be slow..

[gkaplan]

My Firefox problem is that my browser often freezes up.