Firefox 技術支援討論區

When selecting "Open in Firefox" in the "What do you want to do with this file?" box or on about:preferences and then opening a PDF file on the web, instead of downloading the file to RAM and opening it with its online address, Firefox downloads the PDF to /tmp/mozilla_${USER}0 and opens it from there. This also adds it to the download history. I have set the about:config flag browser.download.start_downloads_in_tmp_dir to true so the files I just open and don't want to permanently download don't clutter my $HOME/Hämtningar (downloads) folder. I tried to first prevent that by selecting the default action to do when tasked to open a PDF, but that didn't fix it, so I set the about:config flag. Unfortunately, setting the default action stopped Firefox from opening a PDF inline without downloading it and I cannot find any option along the lines of "Preview in Firefox" (as described in this support article ).

I view a lot of pdf documents via firefox, the light gray background makes my eyes and head hurt after prolonged usage. In the past I found a solution on this forum that advised to set pdfjs.viewerCssTheme to "2" in about:config. This set the background of pdf viewer to black/dark gray. This has worked for years until recently when the pdf viewer switched to light mode again (pic 1). I checked the about:config settings for pdfjs.viewerCssTheme but there appears to be no change. I tried restarting the browser, setting the theme to 0 and to 2 again, updating browser. Sadly the theme is still light gray. Is there a way to change it again? The desired outcome is in pic 2. I do NOT want to change the color of the pdf pages themselves.

Blank Page when clicking on tracking link from UPS website, https://www.ups.com/track?loc=en_US How do I fix this ? Thanks

After the last couple of updates Firefox will not wrap words in view source screen(CTRL+U). This makes the info very difficult to read as most lines of code run off the screen. How do fix this? Thanks.

Hello, I want your help! Because I want to change the appearance of checkboxes to toggles without affecting the other checkboxes (like rounded checkboxes) using userChrome.css in Firefox.

I'm not friend with CSS, because I don't know much about programming. So, please write me a correct CSS code in a comment.

The attached screenshot will explain my demands:

With 'Back up your Firefox data' it says it saves all open tabs.

What is meant by 'open' tabs? Is it tabs that I have clicked on during my session?

I have just over 300 tabs, will Firefox save all of those tabs in the cloud or only the tabs I clicked on during a session?

I am trying to migrate from a very old version of Firefox (v. 55) to the current one, but there is an app that is more helpful to me that all the other features combined. That is the "Tab Grouping" app that will not run in any version of FF higher than v. 55.

In my work, which often includes a tremendous amount of research, I need to be able to quickly go from one group of tabs to another. If I had to open all these sites manually, that would take the better part of the day and frankly I don't have near the mental capacity to remember the tremendous number of tabs. I have had a couple replies (Thanks!) to this question sometime back, but unfortunately none were even close in performance.

So, can anyone direct me to an app that will allow very quick movement from different sets of windows/tab groups (please see screen shots below)? Is there anyway that I can get this app to work in Legacy mode? I have several other old apps that work perfectly well in this mode.

On all sites where I need to login with my work account I get a tab crash when the browser redirects to https://login.microsoftonline.com/ac4b0eb0-811e-4ab0-acca-8a87079290dc/oauth2/v2.0/authorize?response_type=id_token&scope=user.read......

This is a recent failure (this week), that occured without any changes on my own account to Firefox developer version 121.0b2(64-bits)

I had to install google chrome to overcome this problem. Chrome has no issues with microsoft authentication.

Please solve as soon as possible, otherwise I will be switching to another browser.

After updating to version 121, the cursor theme, while having it on the window, changes from the default one (Breeze) to Adwaita while also getting like 2x bigger. How do I change it back to default theme and size?

Is it possible for a big tech company like Apple to release a web platform that is not compatible with Firefox? Firefox is not supported by Apple School Manager (https://school.apple.com) i.e. a web platform designed for educational institutions (PA). Is it legal? Is it possible to make a claim to EU institutions? Thank you

I am unable to install the Bitwarden extension (attempting to do so from the extension's official Firefox page). After prompting me to allow the add-on to be installed, the process hangs. Clearing all data did not help.

Running Firefox 121.0 64-bit on Windows 10.

Thanks.

Hi, I've been using Firefox on all my devices for YEARS without any issues. However, as of recently, I had moved into a new apartment, and with that came a new internet connection, which was very slow since the beginning, but usable.

At first I had assumed that Firefox on my PC was loading websites more slowly because of my poor internet, which was partly the case - however, my laptop and Android phone were on the same network as the PC and were both much faster. So I assumed it had something to do with the differences between WiFi and Ethernet connections - the PC was plugged into the latter while the laptop and phone were using WiFi.

But then I noticed that Firefox was the only program with lacking speeds. Spotify loads video podcasts with no problem, Steam downloads are relatively fast (as much as my network allows), only Firefox took MINUTES to load a simple web site. For example, I tried opening Reddit on my PC to write this post, gave up, and am now writing it on my phone. The Reddit website is still loading on my PC as we speak.

I honestly don't know what could be causing this issue. I checked Task Manager, and Firefox isn't using any more resources than it normally would. I am also using the latest version, I just checked.

Any ideas or fixes? Even diagnosing the problem would go a long way.

I was trying to troubleshoot a black screen of death issue with Windows10 that first started appearing after Firefox adopted the new Private Browsing icon. In the process of doing so, I tried every combination of Firefox settings imaginable. Nothing worked as far as Asus, Windows, or Firefox settings, rolling back/ updating various drivers, etc. So, I decided to refresh Firefox and when that did not work, I decided to uninstall and reinstall Firefox. I'm not sure if that worked as far as the original black screen of death issue is concerned because now Firefox no longer remembers my cookies and site data allowed exceptions (my only exceptions were my bank websites, which worked as expected until the uninstall/reinstall). I've tried selecting always use private browsing and always delete cookies and site data when Firefox is closed (my previous settings), but every time I close Firefox and return those three exceptions are missing. Any ideas would be most welcome. BTW, does anyone know how to use that folder Firefox puts on the home screen labeled "Old Firefox Data" because I was expecting there to be a .exe file to click on to reload all the previous settings in one fell swoop.

I have a Lenovo ThinkPad X1 Yoga Gen 6 (20XY005MGE) with Win11 Pro.

All of a sudden, Firefox does not play any sound. I notice that it does not show up in the volume mixer. I tried:

• this solution: https://support.mozilla.org/de/questions/1278299
• Reboot the PC
• Uninstall and reinstall Firefox
• Deactivate all Extensions
• I worked my way through the manual pages (none of which mentions Firefox missing in the volume mixer)

Youtube does not play sounds, the Spotify page notices that it cannot play sound (the spotify App for Windows works fine, though). News sites (tagesschau.de / video, deutschlandfunk.de / audio) play the video, but no sound.

I had the problem a few months ago already but I cannot recall the solution :(

Thanks for helpful hints!