Firefox Community Forum

Hello to those of you reading this,

Over the last five or so days, my Firefox has been acting in a wholly unpredictable way. Every time I launch Firefox, the inspect element tab will open and close itself repeatedly for about 3-10 seconds, stop for a bit, and then start again. CPU usage by Firefox skyrockets whenever the glitch occurs.

I have tried Troubleshoot mode, I have tried a clean install, I have tried to refresh Firefox, all to no avail. This doesn't seem to have anything to do with a Firefox update, as the last update to my Firefox was well over a week prior to the start of this issue.

I am running several extensions: uMatrix uBlock DuckDuckGo Privacy Essentials DecentralEyes PrivacyBadger BetterTTV Facebook Container Firefox Multi-Account Containers TTV Ad-block Wikipedia Context Menu Search Redirect AMP to HTML

However, none of these seem to be the cause of this issue as it persists in Troubleshoot mode and after a Firefox Refresh.

The only reasonable lead I have regarding this issue is that the browser console spams the error messages as can be seen in the image attached to this post. A recurring element is "server0.conn0.watcher2.process16". I'm afraid I know only enough about coding to understand that this is probably the root of the issue, but am completely lost on how to fix it.

Another tidbit of information, whose relevance I doubt but am including nonetheless, is that I recently transferred my C:/ drive from an SSD to an NVMe. I'm wondering if perhaps the application is trying to call on a process stored on the other drive. I find this unlikely, as similarly to the point on the Firefox version this only started occurring a week or two after I transferred the drive over.

Any assistance on this matter would be greatly appreciated!

I'm on Windows 10. When I try to open the browser, it loads for a second and attempts to open but then crashes and nothing happens. A message box does appear for a second, but it disappears before I can read what it says. I refreshed Firefox and uninstalled and reinstalled the browser, but it is still happening. Firefox works fine on my phone still, so I don't believe it is a problem with my account. I'm also currently doing a virus scan, but it hasn't finished at time of writing.

In the last few days, after some minutes of usage, parts of Firefox become unclickable:

- I can still click on tabs to change tabs. - When hovering over the cross button to close a tab, it changes appearance as it should. Clicking the button does nothing. Ctrl+w still closes the button. - Clicking on the address bar does nothing. - Cannot click on back, forward, refresh buttons. - Cannot click on any add-ons. - Cannot click on preferences. - Can click on the button to open a new tab. There, I can enter an address. Once the page has loaded, address bar becomes unclickable again. - Bookmarks toolbar is still working as expected. - Keyboard shortcuts (ctrl+t, ctrl-w, ctrl-l) still work as expected.

I'm running ``` Mozilla Firefox 138.0 20250428130755 20250428130755 ```

on Manjaro 25.0.1 with GNOME 48

I am running Firefox on Linux. Desktop environment is KDE. Compositor is Wayland. I have a 11th Gen Intel Tiger lake Core i3 with integrated Intel UHD Graphics GPU. I do not have a eGPU or any other GPU apart from the integrated Intel UHD Graphics GPU. Intel drivers are installed and are being used. Please see the details given below from about:support for more details. What I have observed that Hardware acceleration, specifically WEBRENDER_COMPOSITOR, WEBRENDER_SHADER_CACHE and WEBRENDER_DCOMP_PRESENT are disabled. The details are given below.

I have enabled the force hardware acceleration too by setting the property media.hardware-video-decoding.force-enabled to true. But still the above three hardware acceleration are still not available.

How can I get these enabled?

output from about:support GPU #1 Active Yes Description Mesa Intel(R) UHD Graphics (TGL GT2) Vendor ID 0x8086 Device ID 0x9a78 Driver Vendor mesa/iris Driver Version 25.1.3.0 RAM 0

Decision Log HW_COMPOSITING default available OPENGL_COMPOSITING default available WEBRENDER default available WEBRENDER_COMPOSITOR default disabled Disabled by default Blocklisted; failure code

                                                                                                                               FEATURE_FAILURE_DISABLED
                                                       env	        blocklisted	Blocklisted by gfxInfo	
                                                                                               Blocklisted; failure code 
                                                                                       FEATURE_FAILURE_WEBRENDER_COMPOSITOR_DISABLED

WEBRENDER_PARTIAL default available WEBRENDER_SHADER_CACHE default disabled Disabled by default Blocklisted; failure code

                                                                                                                       FEATURE_FAILURE_DISABLED

WEBRENDER_OPTIMIZED_SHADERS default available WEBRENDER_ANGLE default available

                                                       env	        unavailable	OS not supported	Blocklisted; failure code 
                                                                                               FEATURE_FAILURE_OS_NOT_SUPPORTED

WEBRENDER_DCOMP_PRESENT default available

                                                       user	disabled	        User disabled via pref	Blocklisted; failure code 
                                                                                                  FEATURE_FAILURE_DCOMP_PREF_DISABLED
                                                        env	unavailable	Requires GPU process	Blocklisted; failure code 
                                                                                                FEATURE_FAILURE_NO_GPU_PROCESS
                                                       runtime	unavailable	Requires ANGLE	Blocklisted; failure code 
                                                                                               FEATURE_FAILURE_DCOMP_NOT_ANGLE"

WEBRENDER_SCISSORED_CACHE_CLEARS default available

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.

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

Since the last Firefox update, I am unable to sign into my Outlook account. When I click "Sign In" it opens a new tab with the sign-in buttons. Works fine in Edge and Chrome.

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.

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.

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?

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."

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?