I-Firefox Community Forum

https://speedtest.xfinity.com/

I have a 600 Mbps internet connection with Infinity. It measures the speed on Chrome, through my router, however, Firefox only measures the internet speed at approximately 400Mbps. Firefox is slow. I have done all thing suggested to make Firefox perform better. What has happened to this browser? Also the Browser when loaded with too many tabs freezes and has to be forced quit. I started using Vivaldi that measures over 600Mbps. Comments. My laptop is a older iMac that still works perfectly running High Sierra. No more Mac's, Apple has lost it way on producing computers, and has defaulted itself to a phone company.

Attached is a screen shot that shows Firefox trying to measure the speed, but the test has frozen, will not complete.

I am sitting in hospital with a weird problem. The connection is open and thus not secure. I have successfully connected my 2 android devices, however my Windows Asus laptop is being barred by firefox. I only run firefox. It is a dead end because firefox refuses to allow me to access the net at all. So now I have to get my wife to go and download chrome and see whether that will work. Why can I not override as u understand the risks I also use Norton 360 with its VPN.

Hi there my default browser is Firefox Mozilla but certain sites open very slowly or not open at all. All things I did were clean the cache, reinstalling Mozilla software but nothing works and its a bit frustrating. Also Adblock Plus wont work on you tube. Thank you in advance Kuba

My FF browser freezes, suddenly closes all tabs, expands fonts, etc etc All else in my system is normal. Should I just use the default MS Edge and be done with it?

Hello, using Windows 10 Version 22H2 (Build 19045.5965), Firefox 139.0.4, Thunderbird 139.0.2, I can drag multiple emails from Thunderbird but not drop them into Firefox (the stop symbol appears and does not let me finish the action). However, dragging and dropping single emails does work. Firefox does not understand the imap address but the drop is registered which is all that is relevant to me. Is this a bug/missing feature in Firefox or a problem with Thunderbird and Firefox on Windows? Or is there a way to do it by simply adjusting (preferrably very few) settings? Dragging and dropping multiple emails using Thunderbird and Firefox on Linux Mint works fine. Dragging and dropping multiple emails from the Windows Explorer to Firefox also works fine. In testing, the issue only arose using Thunderbird + Firefox, Chromium-based browsers also worked fine with Thunderbird. If this is the wrong forum to ask such a question because this should rather be in a bug tracker or something similar, please let me know. If this should be on the Thunderbird thread instead of Firefox, also let me know. Thank you for your help.

I can open pages but when I click on the subject it doesn't open. Tells error with net work connection, it's like this with email,YouTube and Gmail, twitter. Thank you.

so, basically, if i walk away from my computer for a few hours and firefox is open, I come back to the original window, plus a window for about every hour that i was away. all the new windows are just sitting on the homepage, but this only happens when a keyboard is connected as far as i can tell.

any keyboard by the way, i have now tried it with 12 different ones.(6 different manufacturers at least)

i have tried to refresh firefox, i even went so far as to do the "reinstall but keep my file" thing for windows 11, uninstalled and reinstalled firefox, deleted all the local files, cookies, etc, signing out of my account on the browser, malwarebytes said i didnt have any problems with my system.

I have even tried to figure out how to reset the http and https default to none in windows 11 to attempt to solve this.

the only thing that works so far is to not have a keyboard connected

any help would be great :)

When I copy a post in X from Firefox into a text file, it loses formatting, but when I copy the same post in X from Edge into the text file, it keeps formatting. Why?

I know, sounds stupid, but it is what it is. It happens rarely, only with Firefox on the secondary display from my laptop, via HDMI. It starts with some random few thin horizontal bars across the window itself, and soon, it turns off my display. It seems the bigger the window is, the more severe the issues. So full screen usually, it shuts it off and keeps it off. Not black screen, no signal style. I manage to get it out by Winkey+arrow. If i then put it back same issue. If i lower the width of it, it manages to stay coherent longer, but still resets the display with a quick black screen on page reload. The lower bounds on a 1920x1080 display resolution was 1515 pixels. At 1515 pixels, it works fine, once this is triggered, it's very repeatable on 60-70% of webpages. If i drag another window on top of Firefox, the monitor comes back up.

Before anyone asks: I have tried turning off hardware acceleration. I have tried putting firefox.exe to run on the integrated video card and on the dedicated 1060 Max Q videocard. I have cleared cache and etc.

This persists on a Windows session, across multiple Firefox restarts. A computer restart technically fixes it but i have no clue what triggers it. Laptop monitor works fine.

Hi,

I’m using the latest version of Firefox on Windows 11 (currently v126.0), and I’ve noticed a recurring issue: the browser freezes for a few seconds when I switch between tabs, especially if one of the tabs contains a media-heavy website (like YouTube or online editors).

The browser doesn’t crash, but becomes unresponsive for 5–10 seconds before catching up. Task Manager shows a CPU spike during the freeze. I’ve tried the following:

-Clearing cache -Disabling all extensions -Running in Troubleshoot Mode -Updating graphics drivers

None of these solved the issue.

Is this a known problem? Any suggestions on how to fix or further debug it?

Thanks in advance!

I've loved Firefox for years but can no longer use it because I have been unable to resolve this issue. All was well, an update was done, and bingo, I got this message. I don't know how to fix it. I removed Firefox from my desktop and re-installed. Same 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."

The comment sections for foxnews.com and other sites disappeared using Firefox but not when I switched to Chrome. This just happened 6-18-25. Before this date, it worked on Firefox.

For the past 2 days, Facebook won't load when I try to change my page to another (just switching between accounts). It acts like it is changing or loading, and then I just get nothing. I have done all of the things that are requested from clearing my cache, browsing data, restarting, etc. Nothing is working. I've attached a picture of my screen of I receive when I try to change pages - the big F. LOL Facebook on my phone works fine. I've tried also turning off my VPN and it doesn't load.

I've also had issues with my Xfinity email loading unless I turn off my VPN.

So what is going on?