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Firefox program is extremely laggy and sluggish (Mac)

  • 8 replies
  • 2 have this problem
  • 1385 views
  • Last reply by cor-el

UARH
UARH

About four days ago, I opened Firefox to check my email to find that the program acting extremely sluggish. When I open a new window, the top bars appears mostly blank, lacking any of the bookmarks bar items or add-on icons. After a few seconds, only some of the add-on icons and the leftmost bookmark bar item will appear, and then nothing else. Clicking the address bar, the text cursor doesn't blink, and if I start to type an address, it only populates two letters at a time before lagging for ~10 seconds and populating the next two. Accessing sites is possible, but similarly sluggish, with every action taking ~10-15 seconds before even beginning to load. When attempting to open the in-browser settings menu or anything from the top bar (File, Edit, History, etc.), the button highlights and gets stuck there, and the menu never actually opens.

Long story short, the program is laggy and sluggish. The strange thing is this happened out of the blue, in the middle of the day when I had used Firefox without issue. I don't believe I have automatic updates enabled, and I didn't update Firefox myself, so I have no clues as to why it started acting like this. I've tried uninstalling and reinstalling Firefox several times and tried updating my Flash player. Because of how Firefox is acting, I can't seem to open it in safe mode or figure out another way to turn off my add-ons in case that is the issue.

I'm not the most computer savvy, so I'm kinda at a loss with where to go from here. It's probably not super useful, but I included a screenshot of what Firefox looks like when I first open a window. There are usually several add-on icons and a settings cog-wheel to the right of the search bar, and a dozen or so bookmarks on the bookmarks bar. Any guidance or suggestions would be greatly appreciated!

Thanks!

About four days ago, I opened Firefox to check my email to find that the program acting extremely sluggish. When I open a new window, the top bars appears mostly blank, lacking any of the bookmarks bar items or add-on icons. After a few seconds, only some of the add-on icons and the leftmost bookmark bar item will appear, and then nothing else. Clicking the address bar, the text cursor doesn't blink, and if I start to type an address, it only populates two letters at a time before lagging for ~10 seconds and populating the next two. Accessing sites is possible, but similarly sluggish, with every action taking ~10-15 seconds before even beginning to load. When attempting to open the in-browser settings menu or anything from the top bar (File, Edit, History, etc.), the button highlights and gets stuck there, and the menu never actually opens. Long story short, the program is laggy and sluggish. The strange thing is this happened out of the blue, in the middle of the day when I had used Firefox without issue. I don't believe I have automatic updates enabled, and I didn't update Firefox myself, so I have no clues as to why it started acting like this. I've tried uninstalling and reinstalling Firefox several times and tried updating my Flash player. Because of how Firefox is acting, I can't seem to open it in safe mode or figure out another way to turn off my add-ons in case that is the issue. I'm not the most computer savvy, so I'm kinda at a loss with where to go from here. It's probably not super useful, but I included a screenshot of what Firefox looks like when I first open a window. There are usually several add-on icons and a settings cog-wheel to the right of the search bar, and a dozen or so bookmarks on the bookmarks bar. Any guidance or suggestions would be greatly appreciated! Thanks!

Chosen solution

Good catch. I wasn't, but disabling it didn't fix the issue.

After you suggested that, I went through every section I could find to make sure everything was taken off. I couldn't find anything else and was getting fed up having to use Chrome, so I decided to try refreshing Firefox after backing up my bookmarks. Whatever the problem was, that seemed to work. Is there anything else you would have suggested I try, for other folks who may have similar problems in the future?

Anyways, I really appreciate the help. Thanks so much!

Read this answer in context 👍 0

All Replies (8)

FredMcD
FredMcD

Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?


https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding

https://support.mozilla.org/en-US/kb/firefox-slow-how-make-it-faster

https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-ram

https://support.mozilla.org/en-US/kb/firefox-hangs-or-not-responding

UARH
UARH Question owner

Thanks. When I start it in safe mode it runs fine. What steps can I take from here to try and fix the problem?

FredMcD
FredMcD

It could be the work of one of your add-ons, or it could be Hardware Acceleration. How to disable Hardware Acceleration {web link}

Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; <Control> (Mac=<Command>) <Shift> A)

In the Add-ons Manager, on the left, select Extensions. Disable a few add-ons, then Restart Firefox.

Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All Of them.

If the problem continues, disable some more (restarting FF). Continue until the problem is gone. After, you know what group is causing the issue. Re-enable the last group ONE AT A TIME (restarting FF) until the problem returns.

Once you think you found the problem, disable that and re-enable all the others, then restart again. Let us know who the suspect is, detective.

UARH
UARH Question owner

Thanks for your help, I really appreciate you walking me through this.

Unfortunately, I did all of those things and none of them worked. I removed all of my add-ons and turned off hardware acceleration, but Firefox is still moving slowly when not in safe mode. Thoughts?

FredMcD
FredMcD

Are you using the default theme? If not try it.

https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

Safe Mode is a troubleshooting mode that temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes). If the problem goes away, that tells us one thing. If it does not, that tells us something else.

UARH
UARH Question owner

Chosen Solution

Good catch. I wasn't, but disabling it didn't fix the issue.

After you suggested that, I went through every section I could find to make sure everything was taken off. I couldn't find anything else and was getting fed up having to use Chrome, so I decided to try refreshing Firefox after backing up my bookmarks. Whatever the problem was, that seemed to work. Is there anything else you would have suggested I try, for other folks who may have similar problems in the future?

Anyways, I really appreciate the help. Thanks so much!

FredMcD
FredMcD

That was very good work. Well done. Please flag your last post as Solved Problem so others will know.

UARH said

Is there anything else you would have suggested I try, for other folks who may have similar problems in the future?

Not much else.

cor-el
cor-el
  • Moderator

Maybe disable accessibility services in Firefox.