Firefox Community Forum

I am experiencing significant performance problems in Mozilla Firefox when using certain AI-powered tools. Below are the specific issues:

   Flux AI & Diagramming AI Performance Warnings

       Issue: When accessing Flux AI or Diagramming AI tools, Firefox displays a warning message stating, "This site is slowing down Firefox."

       Observed Behavior:

           Delayed response times or freezing when interacting with these tools.

           High CPU usage (observed via Task Manager) when the tools are active.

       Expected Behavior: Smooth operation without performance degradation, as seen in other browsers (e.g., Chrome or Edge).

   CMS Sign-Out Failure

       Issue: Unable to sign out of my Content Management System (CMS). The action either freezes or refreshes without logging me out.

       Troubleshooting Attempted: Cleared cache/cookies, disabled extensions, tested in Safe Mode—issue persists.

   ChatGPT Menu Error

       Issue: Clicking the three-dots (⋮) menu in ChatGPT triggers an error instead of displaying options.

       Error Context: Mentions "Flux AI," suggesting a possible conflict or integration failure.

can not resolve repeated problem : "The bookmarks and history system will not be functional because one of Firefox's files is in use by another application. Some security software can cause this problem." Cánt not find "Refresh"

So, after using firefox in the background to browse websites or watch videos I checked my memory usage in firefox with about:memory -> Measure and saw that youtube was consuming a decent amount >2GB (checked the main url when clicking the youtube src, it was the video on that sole tab i was watching and nothing else playing youtube in the bg) so i closed that tab, waited a bit and re-measured but then see that the memory usage for youtube rose about 200MB... and the website for youtube is that same url for the tab that i just closed (when checking the src in the results for Measure). I've been revisiting the about:memory page, reloaded it and re-Measured and youtube is STILL THERE. Even now, 10 minutes later i still see youtube there, with none of my tabs running youtube.

If i close firefox entirely and re-open my tabs then it'll very likely fix it but this has to be a major issue no? I shouldn't have to close the entire browser program just to fix a website visit, which is youtube of all websites.

As of this moment, firefox, with 8 tabs open, is consuming 4,452.99MB (~4.5GB) where 2.5GB is youtube for that page i closed.

I don't know if sharing memory reports from the about:memory page give my cookies away or leave me open to a similar vulnerability so I won't share it unless a dev or similar asks for it but for now, I've included an image showing all the tabs i have open on firefox, 2 windows.

Hello there

I'm running version 146.0.1 (64 bit) on a Windows 10 machine, and I've found that trying to use printscreen now opens Firefox. I cannot discern why, if it's a Windows setting or a keyboard issue or anything else

things I've tried:

- Disabling every extension - Disabling AMD Radeon - Disabling ShareX (My normal screenshot program) - Factory resetting my Keychron Q6 Max (in case there's some weird macro that got set up)

Any ideas? This might not be a firefox issue, but I figured I'd ask here. Thank you

I just installed Mozilla VPN but when it's active my internet connection stops working. Pretty sure whatever protocol it's using is the problem with the WIFI signal, but I can't find how to change the protocol like every other VPN service allows. How do I change the VPN protocol? There is strangely no article already on this site for this common problem.

Hiya.

So if I download an attached file on gmail using Firefox... it crashes. If I open up a new tab on Firefox... it crashes. It only started this week.

I'm using 12.7.6 and I really don't want to go back to Chrome, so I hope you can help.

The macbook completely freezes apart from the mouse pointer which moves, but cannot open a thing. Every time I have to turn the macbook off to restart it.

I tried uninstalling and reinstalling the latest version.

Best, Mike

MB is telling me to put MB on Firefox! BUT, I already have MB on Firefox. Can you help me.

Thank you,

Tom Klima [edited email from public forum]

Hi. According to my observations, only Mozilla Firefox and Adobe Reader have this problem so far.

Windows 11 + Multi-Monitoring Windows 10 have this Bug not !

Open Firefox, drag the window to the second or third monitor, and suddenly there is another hidden Firefox window on the taskbar of that display. If you move Firefox back to the main monitor, it disappears again. Or you can close Firefox and restart it on the desired monitor.

This is an annoying little bug, and I don't understand why Microsoft or Mozilla haven't fixed it yet. It's easy to reproduce and has obviously been around for a while. Since it only affects the two programs mentioned above so far, an MS update will probably not fix it; instead, the developers at Mozilla and Adobe need to address it.

Here the Same Topic in Adobe Forum. No bug fix to date

https://community.adobe.com/t5/acrobat-discussions/taskbar-phantom-window-when-using-multiple-monitors/td-p/14390169

I hope you release a bug fix soon... but since that hasn't happened yet, I'm afraid it will take a while... I'm surprised, because I'm sure many people are experiencing this annoying problem, and in my opinion it's not a big challenge for your developers.

@Mozilla Please Fix this Bug. I know Windows 11 is not better than Windows 10 but Supports End and many Users and Customers used in Future this OS and if you don't want to lose any more market share, it's important to fix this minor bug for ordinary users too. Thanks ;-)

Evil Corp (aka Microsoft) updated my Windows 11 PC from 24H2 to 25H2 and now I cannot access quite a few websites (i.e. Amazon, Bank!, etc.) and some take a long time to load (surprisingly, my Firefox Home page...Google...also takes a while to load) . I searched the internet and found many so called fixes and most are very complicated and many contradict others. A lot of them say to disable DNS and reset network stack (using the command prompt) which I do not know how to do even though I worked in the tech business for 40 yrs (mainly data networking)...I retired 20 yrs ago...so I'm old...so I'm not as savvy with computers as I used to be. I tried changing a few Firefox settings, but nothing worked, so I changed them back to the original settings that worked before the update. If someone could give me detailed (and hopefully simple) instructions to resolve this issue, I would greatly appreciate it. I'm am in a bind, so a timely response would be great. Thanks so much, Steve

When I try to load "Comments" I get this message:

Failed loading comments! Please try again...

Trying again doesn't help.

This is a fairly recent problem

Thanks for your help.

I am not able to receive mail from a user sending me mail from a gmail.com account. I have communicated with my ISP Optonline.net and they state the there mail process "checks out" and the issue could be the browser I am using, Firefox. The last email I have from a gmail.com sender was 8/28/2025. I have asked two different gmail users the send me mail and have not received any of them. I have cleared the Firefox cache but that did not correct the issue. I come to you to figure this issue out and hopefully solve it. Thank you Richard Everett [email removed]@optonline.net [phone number removed]

Near Firefox. Why does Firefox's built-in translator always write “Near” in front of all opening sentences? It's very annoying to look at. Have you considered using AI? DeepL is great for translating. It translates not only the words, but also the culture.

[edited email from community support forum]