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My page throws errors in Firefox Nightly such as

Expected color but found ‘undefined’. Error in parsing value for ‘background-color’. Declaration dropped. preview.htm:1:1

and

Expected color but found ‘undefined’. Error in parsing value for ‘color’. Declaration dropped. preview.htm:1:1

The page references ten CSS files besides having dozens of its own CSS declarations. The issue is tha the reference provided to the error (:1:1) does not indicate where I can find the error. That is, I don't know which declaration is at fault. Is there some straighforward way to find the declaration in question?

Hi, when I want to zoom in to the website page, I cant seem to find the horizontal scroll, thus I cant see the left side of the page that I zoomed in. Please make the horizontal scroll available. Thank you.

After new update (135.0a1) my youtube vids starts with audio but NO actual video. Also it timeline constantly extends (like when you move cursor to timeline is extends verticaly and get more light color) and back to grey state.

I tried remove all addons, clear cookies and private windows. Also previewr of video rly buggy and just spams images(?)

Can you add an option to have the menu bar on top instead of the bottom? I rather have it on top like it used to be, so I would like for there to at least be an option to change it.

In my nightly broswer Codeberg opens once when I click to go to a repository the tab keeps loading and does not stop and can't accesss anything then. In Firefox I don't have that problem at all only in Nightly then in Nightly my Facebook emoji's does not show but again in Firefox it does.

Any progress on this? Import bookmarks is already in Firefox android Nightly — export bookmarks should be just as easy, especially for privacy-first users who can't use Sync.

Firefox Nightly for Android

After one of recent update (few weeks ago) cannot access local network ip addresses.

Tried different suggestions from SO in about:config but nothing helps.

Other browsers works.

Hello Im using multiple firefox edition on my PC from beta dev to nightly, and recently in nightly and only nightly I've spotted strange issue that appears as window in window screenshot attached, outer x to close or maximize window does not work only the inner and mostly goes after F11 full screen and then return to normal. Troubleshoot mode and restart does not change or fix this.

The title sums it up. On May 25, 2026 Round Cube email will not allow me to re-enable Dark Reader. It had been working up to that point. I disabled Dark Reader just to see my email without it, then attempted to enable it. Can not. Interestingly, Round Cube in Microsoft Edge will still allow Dark Reader. So, Firefox Nightly the issue?

My Firefox browser (nightly snap 154.0a1 on Ubuntu 24.04) has been misbehaving lately (~2 weeks now) and I'm at a loss why.

First, when I scroll using the mouse wheel, the scrollbar continuously shoots back to the top constantly during scrolling.

Second, when I type text in a Google box and hit enter key, it drops to the next line - like one would expect in a text processing application.

Third, when on YouTube, trying to rewind/forward video instead starts navigating to clickable links. Of particular note (see the attached screenshots) is the appearance of text (such as "Skip navigation" and "Volume" to name a few) - something I've never seen before.

This happens with a new profile as well.

Now, I know that nightly will sometimes have broken items but this is a weird one. I at one time thought the batteries on my wireless keyboard could be responsible but new batteries (confirmed new with a digital multimeter) did not change that.

I'm on Ubuntu 24.04 LTS fully patched. Anyone here with ideas on what it might be?

firefox nightly got update with new look

and there is no "Legacy" option no options for accent color,rounding scale, etc.

i hate it please help me or help me with downgrade

• • When I click application menu or add-ons icons, the menus open to the left of the screen and this is very annoying and inconvenient. Please advise on how to correct this after the update.

I'm not sure what update it was but, new system so I had to go into setting and set things how I like. I cant remove options from additional search engines in settings. This used to be a normal feature. It is no longer one. I want to know how to remove them. Not just disable them, it is not the same. It's fine, If I have to manually recompile the browser to get this done. I just don't want them there. On version 155.0a1 on Arch Linux.

Any constructive help would be greatly appreciated.

Hi, It is not a question but a bug report. From the version 131 up today the Nightly stopped to initialize quickly as before. Certainly, it is not the windows 10 21H2, the antivirus, the firewall or anything other similar internal problem, just because the Edge and the Opera are working fine and they are four times more rapid than the Nightly. It is just to say, that your procedures to improve the security is transforming the Firefox in a mirror of the usefulness Chrome. I take the time to open the home page of Firefox = 9 seconds, against 0.28 s of the Opera. So, I think you should rethink the security and other hidden setting options of the Nightly, because as is, it is very bad. The big thing that the Geeks from silicon Valley did not have in mind is: There are lot of people that need to find extremely fast a configuration, like to export/import passwords from older browsers, or computers, without need to replace one by one. There are many other things that you decided to hide, but I don't know why. Anyway, I will try to update one more time, then, unfortunately I could not use the Firefox anymore. Further, I want a few add-ons, either if there is any percentage of insecurity. A few times we need afford risks to understand and discovery other problems in the web. We cannot do it anymore with the Nightly.

Hi Team, I am using Linux Mint 20 Cinnamon. Cinnamon version is 4.6.6. The issue is that I was browsing and by mistake I selected one tab then dragged it for sometime and then released the tab but that created a new window and now the old windows are not visible in ALT + Tab function. The windows are showing in the Firefox task manager and also the box icon in the top right corner in that "open tabs". Now I am not able to even change the window or able to access the opened tabs. Attached the screenshot and as you can see in that there are total 4 windows showing in firefox and one as active but in the bottom on the firefox icon you can see its only 1 window. How can I access the remaining 3 windows? Found one ticket (https://support.mozilla.org/en-US/questions/1477845) in this the recommend solution does not work. When I try to click on the window 1 tabs then I do not get any response. I tried both the solution but none worked.

Thanks for the help in advance. @Mozilla team member is seeing please check and fix this bug if possible.

Youtube seem to be having problems with video decoding, previous frames seem to be displayed from time to time. for ex, this video: https://www.youtube.com/watch?v=dFhzMEnCEhY

The same profile works on Firefox 134.0b8 (64-bit) without problems, but not on nightly. If I just disable `media.hardware-video-decoding.enabled` and restart, then the problem goes away on Nightly.

Enabling/Disabling my user customizations don't seem to affect it. Enabling/Disabling addons don't affect it. Using a new empty profile also doesn't affect it, the problem persists. I tried deleting "gmp-widevinecdm" folder and redownloading it, still didn't solve the problem.

I seems to be some sort of regression, it used to work before a couple of days ago. Please fix, I hope the information I provided helps, as I like having hardware acceleration.

I also tried to update the display driver. nVidia Driver: 31.0.15.5176 now 32.0.15.6636