Firefox Community Forum

I’ve been using Firefox regularly and overall the experience has been positive, but I’ve noticed a pattern during longer browsing sessions that I’m trying to understand better. When multiple tabs are opened and I switch between them frequently over time, Firefox sometimes becomes less responsive. Pages may take longer to load, scrolling feels delayed, and opening previously loaded tabs isn’t as smooth as it was at the start of the session.

What makes this a bit confusing is that system resources don’t appear to spike significantly, and the slowdown seems gradual rather than immediate. Restarting the browser usually restores normal performance, which makes me wonder if this is related to session handling, memory cleanup, or how background tabs are managed over time.

I’m not necessarily looking for a quick fix, but rather trying to understand whether this behavior is expected and if there are recommended settings or habits that help maintain performance during longer sessions. If others have noticed similar behavior or have insights into how Firefox manages extended tab usage, I’d really appreciate learning from your experience.

Example page used for observation and comparison: https://dunkinmenu.org/

I often keep many tabs open for research, and Firefox memory usage grows significantly over time. Are there practical settings or habits that help manage memory without sacrificing usability?

Hi, I’ve been experiencing slow startup times in Firefox, especially when I have my Time calculator web app open. The browser takes longer to load and sometimes becomes unresponsive.

I’ve tried disabling extensions and changing my home page, but the issue persists. Are there any specific settings or troubleshooting steps in Firefox that can help improve performance when using online calculators like this?

Any guidance or tips would be greatly appreciated. Thanks!

When i start fire fox it immediately opens 10 additional versions in the background which I can see in task manager and they take up a lot off memory. If i end task them they immediately come back. This only started recently. I noticed it because now when i open say a youtube video it shows it as number 4. This never happened before unless I had the same video open more than once.

If I can not stop this I will have to uninstall.

I get screen tearing on videos or when i scroll on any website. Only happens on Firefox, I've tested Chrome, Edge, Opera.

https://streamable.com/80gxcm

Smooth Scrolling is Off. Hardware Acceleration is Off. I've tried toggling "gfx.font_rendering.directwrite.force-enabled" Firefox is up to date.

None of this has helped.

When I brought Firefox up about a week ago, it presented me with a survey, results of which were sent to Firefox developers. They asked several multiple choice questions about features, but they didn't ask a very important question: Would you use Firefox more if it used less system memory? I currently use Google Chrome for about 2/3 of my web browsing because Firefox uses up too much system memory. I would prefer to use Firefox most of the time, but can't, since it bogs down when memory usage gets too high.

The survey should have included a text input box so users could enter any comments for the developers, and the survey did NOT do that.

So, after completing the survey, I was disappointed that I couldn't comment on the most important issue I have with Firefox. I would like the Firefox dev team to try get Firefox's use of system memory down. A short while ago, I opened 4 websites in Google Chrome, then opened the exact same 4 websites in Firefox. The attached shows the memory usage of each browser.

OS: Linux Recently, firefox has been annoying me with not closing a tab when I click the X like normal. I have to right click and close it, or press ctrl w. I am unable to move tabs around, as well. I am not sure since when this next bit has been happening, but I am also unable to interact with many elements of the top bar. The only thing of the firefox ui besides the websites themselves that let me interact with them at the moment is the home button, the new tab button, bookmarked sites, and that box icon on the left corner that lets you look at previously closed tabs. My Firefox's version should around, I believe it is 140.5.0 ESR. Thank you in advance. Update: Upon a restart of firefox, it appears to be working again as normal.. However, the bit with tabs not closing when the X is clicked and not being able to move tabs around has been happening multiple previous times, and it may come back. Update again: The issue does come back after some usage. I'm using KDE plasma with Wayland. I will try what the answer asked, and come back later. Update: This seems to happen very randomly and is not reproducible for me.. It will go a few days being fine, then randomly freeze again. Has not happened under another user, at least not yet.

Firefox has been using more RAM and CPU on my system recently, especially with only a few tabs open. Is this expected behavior, or are there specific settings, extensions, or configurations I should check to improve performance?

Hi!

I've had issues with Firefox now for quite a while and they only seem to be getting worse. Performance is really bad, it's lagging while browsing, especially infuriating when typing as the letters come out at a stuttering pace. I've tried disabling extensions one by one, I've tried troubleshoot mode and experienced no major difference.

If I can't solve this soon enough I won't be able to keep using Firefox, as the experience is so frustrating. And it would be a shame since I've come to like it quite much.

Thanks!

Anyone else having an issue with the newest firefox in Linux Mint? I don't know what's causing it but when multiple tabs open my address bar and all other primary buttons/icons (including the menu button) don't work, only the download button. Across multiple tabs. Not using any groupings/classifications or any "new" tab features or vertical windows etc.

While running Firefox on MacBookAir with macOS 15.7.2 to browse simple websites I keep getting the below warning message. I may have 2 or 3 other apps open (like Apple Mail, MS-Word, Preview). "Heavy memory usage You're running out of memory and your Mac may become noticeably slower. Consider quitting some applications. Firefox 2,48 GB" So I quit Firefox to re-open again and continue my work. Does somebody has an hint where this message can come from ? Any settings to change on my MAC ? Thanks for helping

What causes Firefox to freeze when two video windows are opened, i.e. in a new tab, the video windows immediately start to freeze? I use Windows 11. Other browsers work fine, only Firefox freezes with two windows open.