Is the bar on the bottom?

This is a custom style rule for userChrome.css that I've experimented with. Its goal is to allow the system bar at the bottom to remain visible, and is sized for my display on Windows 10. I have no idea whether it would be useful for Linux.

/* Set max-height for fullscreen so Taskbar is visible */
#main-window[inFullscreen="true"], 
#main-window[inFullscreen="true"] #content-deck {
  /* Set your screen height */
  --my-screen-height: 1200px;
  
  /* Set your taskbar height, this is Windows 10 */
  --my-taskbar-height: 50px;
  
  /* Set your devicePixelRatio, for example visit
 https://www.jeffersonscher.com/res/resolution.php
 at 100% zoom and set the following to match your 
 window.devicePixelRatio */
  --my-devicePixelRatio: 1.25;
  
  /*** COMPUTED VALUES ***/
  --screen-avail-above-taskbar: calc(var(--my-screen-height) - var(--my-taskbar-height));
  max-height: calc(var(--screen-avail-above-taskbar)/var(--my-devicePixelRatio) - 2px) !important;
}

Probably someone else has developed a more elegant approach. A good place to get help with tricky style rules is:

https://www.reddit.com/r/FirefoxCSS/

And for more background on userChrome.css files, I have a site here:

https://www.userchrome.org/

Thank you for your answer, I don't think that applies to my case though. What I aim for is, instead, something as similar as possible to Google Chrome's "app mode" (which you obtain, for example, by running chrome with the flag `--app` from the command like). I found this firefox extension that does something similar but has two problems:

• it still has a title bar
• it's glitchy and by default popup in my window manager

In the end I found a hack to solve this in my specific setup. Thank you anyway!

Hi harisont, if you think anyone else might be interested in the same thing, feel free to share your technique here.

You can use this code in the Browser Console to toggle the navigator-toolbox off/on in the currently selected window.

• https://developer.mozilla.org/en-US/Tools/Browser_Console

You can hide the title bar via the customize page.

(function(){ /*toggle toolbox*/
var doc = Services.wm.getMostRecentWindow("navigator:browser").window.document;
var nt = doc.getElementById("navigator-toolbox");
var ds = nt.style.getPropertyValue("display") == "none";
nt.style.setProperty("display",ds?"-moz-box":"none","important");}
)()

My solution is a bit hacky and quite specific to my setup as I'm running i3 as a wm, but in case it's useful for anyone else: - install the "New window without toolbar extension" (link is above) - change your i3config file so that you disable floating and borders on windows with class "Firefox" (with capital f) (basically, add this line: for_window [class="Firefox"] floating disable border none)

Did you try the code I posted above in the Browser Console?

Actually I didn't, because my solution does exactly what I want in my setup, but thank you for posting it, it may be very useful for someone else!