---
title: Live Editing Zen Theme
lastmod: 2024-09-17
---

This [[guides/index|guide]] will help you customize the appearance of Zen Browser by live editing the `userChrome.css` file. Follow the steps below to start customizing your browser's theme.

## Step 1: Access the Profile Folder

1. Open Zen Browser.
2. Type `about:support` in the address bar and press Enter.
3. Look for the **Application Basics** section.
4. Click on **Open Profile Folder**. This will open the folder where Zen Browser stores your user data.

>[!warning]
> On the Flatpak version of Zen, the profile folder will be located at `~/.var/app/app.zen_browser.zen/.zen`.

## Step 2: Create the `chrome` Folder

1. In the Profile Folder, create a new folder and name it `chrome`.
2. Inside the `chrome` folder, create a new blank file named `userChrome.css`.

## Step 3: Open Style Editor in Zen Browser

1. In Zen Browser, press `Ctrl + Shift + Alt + I` to open the Developer Tools.
2. Navigate to the **Style Editor** tab.
3. In the filter/search bar, type `userChrome` to locate the `userChrome.css` file you created earlier.

>[!warning] How do I enable the Browser Developer Tools?
>After Zen Browser version `1.0.0-a.31` the Browser Developer Tools is **disabled** by default for security.
>1. Open the `about:config` page. This page contains advanced settings for the browser.
>2. Search for `devtools.debugger.remote-enabled`
>3. Toggle the setting to `true` by double-clicking on it


## Step 4: Edit the `userChrome.css` File

1. The `userChrome.css` file should now be visible in the Style Editor.
2. You can start editing the file directly within the Style Editor.
	 - **Note:** You can use the **Inspect** button  ![[inspect.png]] to hover over and select elements on the page. This allows you to learn about the `id`, `class`, or other attributes of elements, which you can then target in your `userChrome.css` file.
1. To apply your changes, save the file by clicking **Save** or by pressing `Ctrl + S`.

> [!warning]
>  If a style does not apply as expected, try adding the `!important` keyword at the end of the CSS rule. This forces the browser to apply the style regardless of any other existing styles.

> [!tip] 
> If you wish to edit pop-ups or menus that automatically hide, be sure to enable the `Disable Popup Auto-Hide` option from the *Browser Toolbox* settings menu ( ⋯ button )

Any changes you make to the `userChrome.css` file will be applied immediately to Zen Browser.
Use this file to customize various UI elements, such as colors, fonts, and the layout.

You can use this guide to help you [[themes-marketplace| create your Zen theme and publish it.]]

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This guide is designed to help you quickly and efficiently customize your Zen Browser experience. Happy theming!