Firefox Community Forum

Hi, I’ve noticed that Firefox often uses a lot of memory when I have multiple tabs open, even more than Chrome or Edge on the same number of tabs. Sometimes it slows down my system or makes switching between tabs laggy.

Is this normal behavior, or is there a way to reduce Firefox’s RAM usage without losing performance? Are there specific settings, add-ons, or troubleshooting steps I should try?

Thanks in advance!

I use both Firefox and Google Chrome. My mouse works fine with Chrome but with Firefox there are frequent long delays (60-120 sec.) when moving from one web site to another. The mouse just freezes up and I have to struggle to close Firefox. No problem with the mouse with Chrome, but I prefer Firefox and its features. Any suggestions?

I opened Firefox on one of my computers as usual today but the whole performance changed. Used to go to my home tab and select various news sites to see what was happening. First, when I scroll down the bookmarks, I would hit the "news" and click on it so all the sub items would stay in the scroll, but instead of that, it wanted to open every item as a new tab. When I finally started opening the various news outlets, it opened them in new tabs, it had always opened in the same tab. Then, I couldn't close the various tabs it had opened. I would go to the tab and hit the "X" but it didn't close the tab. I had to use a drop down menu to close a tab. And when in a site, I used the scroll button on the mouse, instead of scrolling, it made the page larger or smaller instead of going up or down. What could make such a change in behavior? I opened up the 'settings' on it and looked at 'tabs' and they were the same as the ones that are on this computer that works as expected. Both computers have it set to open all previous windows and tabs. Both have the same settings for 'tabs' and 'browsing'. I don't get it. Both are version 143.0.3 (64-bit) I have Ubuntu OS.

Macbook Pro using Tahoe 26.0.1; desktop freezes when Firefox 140.3 is active. Desktop icons do not work. Firefox has to be shutdown for the desktop icons to work.

Hi,

When i switch between two tabs by clicking with my external mouse ( I am on one tab and then point and click on another) and then directly start to scroll the page zoom like it does when i hold ctrl+zoom. What causes this?

It does not do the same in other browsers or other apps. It does the same with external mouse and track pad.

Win 11 Pro Firefox 143.0.3 (64-bit)

I'm running the latest version of Windows 10 and Firefox 143.0.1.

I recently bought my first OLED monitor, so I enabled auto-hide taskbar in Windows to try and reduce the chance of burn-in. However, while it works for the most part, it seems to often break in Firefox where the taskbar will hide, but not reappear when I move my mouse pointer to the bottom of the screen.

You can replicate this issue by having FF not maximised, then dragging its window titlebar to the top of the screen and letting go in order to maximise it. At that point, the taskbar no longer pops up when you mouse over the bottom of the screen.

Many thanks for any help you can give.

I know this probably sounds odd but I'm not imagining it. I like many people I live with many tabs open at once. Since the 143 update I come back to my computer the next morning and many of my tabs, specifically my gmail tab and many others will not work. (Oddly I've noticed some random tabs will still work, I have no idea why) I can close the tab and try to reopen gmail in a new tab and it just sits there trying to open but it will not. I've waited 20 minutes. Not until I close firefox and restore my last session will it again work properly. Is there a bug/glitch or is there some setting I need to adjust. I don't want to have to close my firefox everyday. Edge is not having this same issue, so I'm pretty sure it's not a problem with my specific machine. It's like Firefox just decides to quit when I go to bed. I know it sounds crazy.

Watching CNN on Youtube suddenly freezes the tab. Randomly. Freezing means nothing can be done. The video simply stops without reloading or buffering. The mouse reacts, the pointer will activate ie highlight a button under the mouse, but when I click a button nothing happens. The tab freezes and nothing can be done. I can't even access the URL or search box. Nothing. I tried moving the tab itself or into another browser window, nothing. This tab is dead. Opening the same video in a new tab works like normal. I tried the usual things like deactivating Bitdefender, but no luck. Any ideas?

When I click the Firefox icon on my taskbar, it apparently starts OK, but in a second or so the window dims (See first attached image). This window doesn't allow any typed input anywhere, and doesn't close when I click the X in the upper left. This window can be made to go away either by using the Task Manager or by right-clicking on the taskbar icon and selecting Close Window.

However, if I right-click the taskbar icon and select Open New Window, the resulting window appears undimmed (Second attached image) and works correctly.

The above behavior is new; I've used Firefox for years with no problem.

The other user on this machine doesn't see this behavior at all.

Hi,

I recently updated Firefox to the latest version on Windows 11, and since then the browser keeps freezing randomly while browsing. Sometimes it becomes unresponsive when multiple tabs are open, and I have to force close it.

For example, yesterday I was checking a food site with the Dunkin Donuts Menu, and the browser completely froze when I tried switching between tabs. I already tried clearing cache, disabling extensions, and even refreshing Firefox, but the issue still comes back.

Has anyone else experienced this problem after the recent update? Any guidance on what else I can try would be appreciated.

Thanks in advance.

https://www.mlb.com/gameday/braves-vs-nationals/2025/09/17/776286/live

this site at mlb.com or any site showing a live game eventually freezes up and cannot be closed normally. task manager or re-boot is only way out, starting over with a new instance of firefox after ending all firefoxes.

this has been happening just this past few days, after firefox updated to 143.0 on windows 11 using defender, no other screwed up security software.

firefox needs to fix this, it is not likely anything with the site but rather with firefox latest update, as this has always worked before on this same computer.

Dennis Coleman

It takes almost a minute for my home page to come on after I click on My Firefox icon. That has only started happening in the last week or so. But . . . also . . . when I sign into my email account with my ID and complete password, even though I check the "stay signed in" box, that does not happen. I need to fully sign in each time, and that, too, time-wise is somehow related to the delay in getting my home page up. On several occasions I have gotten a message that Firefox is not responding. Thanks for any help you can give. I have Windows 11.