Diễn đàn hỗ trợ Firefox

Hi there,

Is it possible to change the padding of menu items in both the menu bar menus and context menus with userChrome.css?

Please see attached images.

Thanks.

I had the same problem as, for example, this:

 https://support.mozilla.org/en-US/questions/1375244

firefox (on linux) was unable to open a file browser to the local filesystem on clicking a website-provided button for file uploads, e.g. here https://video-converter.com/

I have seriously messed up with firefox settings over the years in order to safeguard my privacy, against all the attempts by firefox to infringe it. (Admitteddly, not as much as google chrome, safari and, got forbid, m$ edge). One of these fixes was to link the file/database content-prefs.sqlite (found in my firefox profile dir) to /dev/null. It was this that caused a problem with the file browser not showing. WOW!

Once I deleted said file (linking to /dev/null). Firefox started and all was OK wrt the file brower.

That caused me to create a script to be run before and after firefox launch, searching for all these privacy-infringing databases in my profile dir and erasing them.

The steps to this are: 1) edit /usr/share/applications/org.mozilla.firefox.desktop and replace all Exec=firefox entries with Exec=/usr/local/bin/firefox-custom.sh 2) create a new file /usr/local/bin/firefox-custom.sh with this content

1. !/bin/bash

CMD="firefox" if [ -x ~/bin/firefox-custom.sh ]; then CMD=~/bin/firefox-custom.sh fi echo "$0 : executing firefox with this command :" echo " ${CMD} $*" ${CMD} $*

3) create a ~/bin/firefox-custom.sh file with this content

1. !/bin/bash

function eras { local f="$1" echo "erasing file '$f' ..." rm -f "${f}" }

echo "$0 : on starting, erasing various sensitive firefox databases ..."

while IFS= read -r afil && -n "$afil" ; do eras "${afil}" done <<< "$(find ~/.mozilla/firefox -type f -name 'content-prefs.sqlite')"

echo "$0 : now executing firefox ..." firefox $*

echo "$0 : on exiting, erasing various sensitive firefox databases ..." while IFS= read -r afil && -n "$afil" ; do eras "${afil}" done <<< "$(find ~/.mozilla/firefox -type f -name 'content-prefs.sqlite')"

lanuching firefox now either from a desktop file (e.g. via Plank launcher) or from the command line: gio launch /usr/share/applications/org.mozilla.firefox.desktop runs the above script before and after firefox running.

Disclaimer: the above script erases files in your profile directory, use at your own risk. Perpahs make a backup copy of your profile dir before.

Is there a way to make the URL high lighting of the domain more obvious? I find that most people can barely see the highlighting and I'd like to make it obvious (bolder and red, or highlighted in yellow, for instance.)

Can this be done via userchrome.css?

Thanks,

Thane

Hello,

as per description I noticed that firefox version 138 requires an ArrayBuffer as the argument of WebAssembly.compile() and doesn't allow anymore (like in 137) a SharedArrayBuffer, is this intended or it will be fixed in the future? Follows a simple test case. Kind reagards.

--- index.html --- <title>Example</title> <script> let instance = undefined; async function loadWasm() { try { const response = await fetch('./sum.wasm'); const buffer = await response.arrayBuffer(); const sharedBuffer = new SharedArrayBuffer(buffer.byteLength); const tmpView = new Uint8Array(sharedBuffer); tmpView.set(new Uint8Array(buffer)); const module = await WebAssembly.compile(sharedBuffer); instance = await WebAssembly.instantiate(module); } catch (error) { alert(`failed to compile in wasm: ${error.message}`); } } loadWasm(); function testWasm() { if (instance) alert(`sum 1 + 2 = ${instance.exports.add(1, 2)}`); else alert('invalid instance, failed to compile'); } </script> <button onclick="testWasm()">Press to run wasm function (sum)</button> --- ---

--- sum.wat --- (to convert into .wasm using: wat2wasm sum.wat -o sum.wasm) (module (func $add (param $lhs i32) (param $rhs i32) (result i32) local.get $lhs local.get $rhs i32.add) (export "add" (func $add)) ) --- ---

Hi all,

I’ve been using Firefox for a while now, but coming from Chrome, I’m finding some aspects of Firefox’s cache management and tab behavior a bit inconvenient, and I wanted to share my thoughts.

The issue:

When I restart Firefox (version 133.0.3-1), it loads webpages from the disk cache, which is fine because I’ve set browser.cache.disk.enable to true and browser.cache.check_doc_frequency to 2, it will always make a request to the server on restarting Firefox with the default value of 3. However, the problem arises when I open new tabs — they also load from the disk cache instead of requesting fresh content from the server.

What I’m looking for:

   A way to have Firefox:

Load webpages from the disk cache when restarting the browser (which I want, and I have set browser.cache.disk.enable to true for this). But always make fresh requests from the server when opening new tabs, no matter what the cache settings are.

In Chrome, this behavior is more intuitive — it loads from the cache after restart but always fetches from the server for new tabs, which I find to be much more reasonable.

I understand that about:config provides settings like browser.sessionstore.restore_on_demand, but adjusting this option makes Firefox fetch content from the server for all tabs, including those opened after a restart. This doesn’t seem like a perfect solution because it takes away the ability to use the disk cache after restarting the browser.

I would really appreciate it if Firefox could offer more granular control over this behavior, so users could get the benefits of both caching and real-time requests based on the type of tab (restart vs. new tab).

Thanks for your attention, and I hope to see some improvements in future updates!

Steps to recreate:

1. Open any website
2. Make any css changes. These will be shown in the Changes tab in the dev tools
3. Close dev tools, then re-open. Now those changes won't be shown

Sometimes I need to close dev tools in order to see how the web page would look normally.

After typing in about:config and clicking on the 3 lines top r.h. corner I'm supposed to get a page that list preferences. (using Wndows 11) That page does not appear. I wish to change my value for width scrollbar width from zero to 4. I have also accessed videos - with sound -but find i very hard to follow the voice of the presenter because he/she talks far too fast, and in many instances is outdated! I need a page on screen that tells me to type in specific keystroke to get to the page that lists a preference I can change.

Hello.

In about:config the keyword.enabled false does not work anymore.

So how on earth do we stop this stupid search option in the url bar. When i open a new tab, i'll get on a firefox tab. In the middle I can search (in the search bar), but after typing 1 letter, the search is moved to be in the address bar. WHY????

How to stop this madness?

Thank you for an answer

I want to change this option :

.pdfViewer .page {

 /* border: var(--page-border); */
 border: 0;

}

to remove the borders between pages in the pdf viewer. I tried doing this in the userChrome.css file but it didnt work.

Hello!

I would like to dump Chrome and return to using Firefox. I just would like to know if it's possible somehow to remove about:mozilla page from within a browser (it's important for me). If anyone knows of a way to do it - please let me know.

Thank you!

This button that looks like a jig saw bit will not budge.

Can I delete this in about:config by deleting the 'unified extention button' and can I delete the 'HKLM/SOFTWARE/Wow6432Node/Mozilla/Firefox/Extensions' in the registry?

Firefox these days is getting a burden with more info and such like being collected behind out backs, it's about to be ditched on all my computers, the last few episodes make me want out.

Dave.

I have to manually change the layout.css.devPixelsPerPx setting evertime I switch from my laptop to an external monitor. What can I do to avoid this every single time?

Hello,

I have an issue where, when I switch tabs with Ctrl+Tab, my mouse cursor accidentally triggers something if it happens to be in the center. This is very annoying. I tried Googling how to turn off tab visualization through the config, but it hasn't worked so far.

   * browser.ctrlTab.previews

• browser.tabs.closeWindowWithLastTab
• browser.tabs.animate
• toolkit.cosmeticAnimations.enabled

So now, the only option I see is to turn off Recent Tabs, but then the browser becomes unusable. I also tried the same on a new clean user profile and even on new Mozilla-based browsers, but still nothing. It would be ideal to make the cursor inactive while switching tabs, like it is in Arc Browser and probably many others. But I would be happy enough to just turn off tab switching visualization.

Changing Default Behavior (CSS)

When I'm reading on a computer screen, I hatehatehatedespisehatehatehate "widow and orphan" control. This is especially annoying when reading a long narrative passage that reflows so that a break (often a blank paragraph) falls at the bottom or top of a column/page. There are two relevant CSS properties, each taking a nonzero positive integer as an argument:

    widows: [number of lines]
    orphans: [number of lines]

It appears that Firefox has (like most browsers) established a "default" value of 2 in each of these parameters, which seldom appear in site-specific stylesheets. Do Not Want.

Is there a way to change this default behavior to the equivalent of:

    body {
         widows: 1;
         orphans: 1;}

without either (a) breaking anything or (b) having to redo whatever change every time there's a Firefox update?

new Date(1743623960000).toLocaleString(['en-ES'])

outputs "4/2/2025, 7:59:20 PM" in normal firefox and "2/4/2025, 7:59:20 PM" in Firefox Developer. Test on MacOS and Ubuntu.

Hello,

I have been experiencing this issue for a while, but only just now noticed it. When I hover over a tab, nothing shows up; no preview, no title, no web address, nothing. I have a few extensions, but uninstalled any that would effect tabs at all, with no change. All other extensions I have had since I switched over to Firefox. I have attempted to search for solutions, and have followed what I found. Multiple support questions here have gotten the answer of going into the config to change the following Boolean variables to be true:

   browser.tabs.hoverPreview.enabled 
   browser.tabs.hoverPreview.showThumbnails 

but when I went to do so, they were both already set to true. I disabled and then re-enabled them just to check, but nothing changed. I have a ridiculous amount of tabs open, but that's the only other thing I can think of that would be causing this issue. Just in case, I am in the process of closing as many as I can.

Any advice or assistance would be appreciated.

Thank you.