docs/content/docs/guides/about-config-flags.mdx

---
title: Hidden/Advanced Preferences
description: A list of useful flags in Zen Browser's Advanced Preferences page (about:config).
---
These are a variety of settings that can change Zen's appearance, behavior, and more. To access them, go to `about:config` in Zen Browser, and search for the title of the flag. Some of these flags may require a restart to work.

### Appearance
#### `zen.theme.content-element-separation`
Changes the size of the border around the browser window. 8 by default.
#### `zen.theme.accent-color`
The color hex value of Zen's main accent color.
#### `zen.theme.essentials-favicon-bg`
Enables a colorful icon for when an essential tab is selected, based on the website's favicon. Enabled by default.
#### `zen.theme.gradient`
Allows setting custom sidebar colors. Enabled by default.
#### `zen.theme.gradient.show-custom-colors`
Allows setting a color hex as your sidebar color. Disabled by default.
#### `zen.view.experimental-rounded-view`
??? Disabled by default.
#### `zen.view.gray-out-inactive-windows`
If a window is inactive, the theme color fades to gray. Enabled by default.
#### `zen.watermark.enabled`
Shows a splash screen briefly when Zen is opened. Enabled by default.

### Transparency & Blur
#### `zen.theme.acrylic-elements`
Windows-specific. Allows use of Windows' Acrylic protocol for a blur effect in Zen. Enabled by default on Windows.
#### `zen.widget.linux.transparency`
Linux-specific. Makes the browser UI transparent.
#### `browser.tabs.allow_transparent_browser`
Changes the default website background to your theme color. Disabled by default.
<Callout type="warn">
Enabling could break the way certain websites look.
</Callout>

### Tabs
#### `zen.tab-unloader.excluded-urls`
A comma-separated list of URLs exempt from being unloaded.
#### `zen.tabs.dim-pending`
Dims unloaded tabs. Enabled by default.
#### `zen.tabs.rename-tabs`
Allows renaming pinned tabs. Enabled by default.
#### `zen.ctrlTab.show-pending-tabs`
Allow switching to unloaded tabs using Ctrl+Tab, when "Ctrl+Tab cycles through tabs in recently used order" is enabled. Disabled by default.
#### `zen.startup.smooth-scroll-in-tabs`
Turns on smooth scrolling when scrolling through tabs. Enabled by default.
#### `toolkit.tabbox.switchByScrolling`
Allows to switch tabs by scrolling when hovering over tabs. Disabled by default.

### New Tabs
#### `zen.urlbar.replace-newtab`
Replaces opening a new tab, with instead showing the URL bar and allowing you to input a query which will then open a new tab. Enabled by default.
#### `zen.workspaces.open-new-tab-if-last-unpinned-tab-is-closed`
Opens a new tab when all pinned tabs are unloaded, and all tabs are closed. Disabled by default.

### URL Bar
#### `zen.urlbar.hide-one-offs`
Hides the alternative search engines from appearing in the URL bar. Enabled by default.
#### `zen.urlbar.show-domain-only-in-sidebar`
When Single Toolbar is enabled, shows only the website domain(ex: example.com) instead of the full URL(ex: example.com\/page). Enabled by default.
#### `zen.urlbar.show-protections-icon`
Shows the "protections" icon in the URL bar, which details security information about the current website. Disabled by default.
#### `zen.urlbar.wait-to-clear`
How long the URL bar saves what you typed, if you typed something in and unfocused it in milliseconds. 45000 by default.

### Sidebar
#### `zen.view.sidebar-collapsed.hide-mute-button`
Hides the mute button in Collapsed Toolbar mode.
#### `zen.view.sidebar-expanded.max-width`
Controls the width of the sidebar in Single Toolbar or Multiple Toolbars mode.
#### `zen.view.sidebar-height-throttle`
??? 200 by default.

### Window Controls
#### `zen.view.hide-window-controls`
Hides the window controls. Enabled by default.
<Callout>
In Single Toolbar mode, this hides the toolbar, which can then be revealed on hover.
</Callout>
#### `zen.view.experimental-force-window-controls-left`
Forces the window controls to appear on the left side of the window. Disabled by default.
<Callout>
If the sidebar is in the left side, it will appear in it.
</Callout>
#### `zen.view.experimental-no-window-controls`
Removes the window controls entirely. Disabled by default.
<Callout>
This will disable the toolbar in Single Toolbar mode.
</Callout>

### Workspaces
#### `zen.workspaces.swipe-actions`
Allows swiping with the trackpad on the sidebar to switch workspaces. Enabled by default.
#### `zen.workspaces.wrap-around-navigation`
When swiping through tabs, allow going to the last workspace from the first workspace by swiping left, or vice versa. Enabled by default.
#### `zen.workspaces.natural-scroll`
Turns on natural scrolling for swiping through workspaces. Disabled by default.
#### `zen.workspaces.scroll-modifier-key`
Controls the hotkey that enables hovering over the sidebar and switching workspaces by scrolling. Options are 'ctrl', 'alt', 'shift'. Default is 'ctrl'.

### Compact mode
#### `zen.view.compact.animate-sidebar`
Animates the webpage moving in/out when compact mode is enabled/disabled. Enabled by default.
#### `zen.view.compact.color-sidebar`
Colors the sidebar with your custom theme color during compact mode. Enabled by default.
#### `zen.view.compact.color-toolbar`
Colors the toolbar with your custom theme color during compact mode. Enabled by default.
#### `zen.view.show-background-tab-toast`
Shows a toast when a tab is open while compact mode is enabled. Enabled by default.
#### `zen.view.compact.show-sidebar-and-toolbar-on-hover`
Shows the sidebar/toolbar if you hover in their general area during compact mode. Enabled by default.
#### `zen.view.compact.toolbar-flash-popup`
Shows the sidebar for a moment when opening a new tab during compact mode. Disabled by default.
<Callout type="info">
`zen.view.compact.toolbar-flash-popup.duration` controls the duration in milliseconds. 800 by default.
</Callout>
#### `zen.view.compact.toolbar-hide-after-hover.duration`
Controls the duration until which the toolbar/sidebar hides after you stopped hovering over it in compact mode. 1000 by default.

### Split View
#### `zen.splitView.enable-tab-drop`
When enabled, dropping a tab from the sidebar to the current webpage starts split view. Enabled by default.
#### `zen.splitView.min-resize-width`
The minimum width or height of any split view tab. The number represents the percentage of the screen taken up by the tab. 7 by default.
#### `zen.splitView.rearrange-hover-size`
??? 24 by default.

### Media
#### `zen.mediacontrols.enabled`
Shows a media player interface if audio is playing in another tab, or a conference call interface if you're in a conference call. Enabled by default.
#### `media.videocontrols.picture-in-picture.enabled`
Allows picture-in-picture. Enabled by default.
#### `media.videocontrols.picture-in-picture.enable-when-switching-tabs.enabled`
Automatically turns on picture-in-picture when switching tabs during video playback. Disabled by default.

### Other
#### `zen.keyboard.shortcuts.enabled`
Allows changing keyboard shortcuts. Enabled by default.
#### `zen.glance.open-essential-external-links`
When enabled, external links that are opened inside an essential tab will open in Glance. Enabled by default.
#### `browser.toolbars.bookmarks.visibility`
Controls when the bookmarks toolbar is shown. Options are 'always', 'newtab', 'never'. Default is 'never'.
#### `zen.downloads.download-animation`
When enabled, plays an animation when a download begins. Enabled by default.
<Callout type="info">
`zen.downloads.download-animation-duration` controls the duration in miliseconds. 1000 by default.
</Callout>
#### `zen.haptic-feedback.enabled`
macOS-specific. Triggers haptic feedback on the trackpad's vibration motor when you drag tabs around, or change the texture in the Change Theme Colors pop-up. Enabled by default.
#### `zen.browser.is-cool`
This is true.