Clean Firefox User Interface with Vertical Tabs

I spend a lot of time in Firefox. This post is a summary of how I configure it for productivity and efficiency. I am maintaining this configuration across three macOS computers, writing down the configuration helps me to make this consistent. As always: highly subjective and subject to personal taste.

Main ingredients for my "less is more" configuration:

This is the result of the configuration from this post:

Firefox Screenshot

This configuration removes the Firefox title bar, including the window modification buttons (red, yellow and green dots on macOS). This is on purpose. I run Firefox nearly always with a single maximized window, so the window modification buttons are not really needed. If needed, I close a Firefox window via the menu (File → Close Window), same with minimizing a Firefox window.

Firefox theme is Nord Polar Night.

Install and Configure Sidebery

In Firefox, go to the Sidebery Addon web page and install the add-on.

Sidebery has a lot of configuration options. Most of the defaults are fine and do not need tweaking. Starting from default settings, in Sidebery settings adjust this:

Settings - General:

Settings - Navigation bar:

Settings - Tabs:


Styles editor - Tabs:

.Tab[data-discarded="true"] .body {
    opacity: 1;
.Tab[data-discarded="true"] > .body > .fav,
.Tab[data-discarded="true"] > .body > .t-box {
    opacity: 1;

Configure Firefox

Hide Firefox Tab Bar, Title Bar and Sidebar Header

Hiding the Firefox tab and title bars is not possible through configuration, this needs a custom userChrome.css file.


/* hides the native tabs */
#TabsToolbar {
  visibility: collapse;

/* hides the title bar */
#titlebar {
  visibility: collapse;

/* hides the sidebar header */
#sidebar-header {
  visibility: collapse !important;

Done. Enjoy a clean Firefox.

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