Frequently Asked Questions

ungoogled-chromium Wiki

Table of Contents

Can I install extensions or themes from the Chrome Webstore?

Yes, but not via the Chrome Webstore interface. Instead, the URL used by the Webstore to download CRX files (Chrome/Chromium extension packages, used by all extensions in the Chrome Webstore) can be used.

Downloading the CRX file

CRX files are downloaded using the following template CRX URL:,crx3&prodversion=[VERSION]&x=id%3D[EXTENSION_ID]%26installsource%3Dondemand%26uc


  • [EXTENSION_ID] is the extension ID from the Chrome Webstore. This can be retrieved from the Chrome Webstore URL for that extension, which has the form[...]/[EXTENSION_ID]
  • [VERSION] is the Chromium browser version.

For example, cjpalhdlnbpafiamejdnhcphjbkeiagm is the extension id of uBlock Origin, and 69.0 is for the 69.0.x.x browser versions.

This URL can be used directly by CLI utilities like curl and wget, but it can also be used via a custom search engine.

  • To set up the custom search engine, create a new entry in chrome://settings/searchEngines, using the template CRX URL as the search URL above after replacing [EXTENSION_ID] with %s. Then, set chrome://flags/#extension-mime-request-handling to Download as regular file.

Installing the CRX file

There are several methods to install CRX file:

  1. Always install extension MIME type requests

    Change the flag chrome://flags/#extension-mime-request-handling to Always prompt for install. Then when using the CRX URL from the omnibox or the custom search engine, the browser will prompt for installation.

  2. Drag and drop

    NOTE: There are certain circumstances where this method fails on KDE Plasma.

    NOTE for Chromium 67 and newer: If the Material Design page is used (which has been default before 67), “Developer mode” of chrome://extensions/ (a switch at the top right corner) must be enabled for drag and drop to function. (Discovered in #423)


    1. Have the CRX downloaded to your file system
    2. Open chrome://extensions
    3. Drag-and-drop the CRX from a file browser into the page of the extensions tab. While dragging over the page, it should state to drop the file to install.
  3. External Extension Descriptor (Linux systems only)

    This example assumes the CRX is downloaded as /home/share/extension_1_0_0.crx. Modify the path as necessary.

    To install an extension with ID aaaaaaaaaabbbbbbbbbbcccccccccc, create the file


    with following content:

         "external_crx": "/home/share/extension_1_0_0.crx",
         "external_version": "1.0.0"

    After restarting the browser, the extension should be loaded automatically.

This FAQ answer was adapted and extended from Inox browser.

Do plugins work?

Yes. All plugins including PepperFlash and Widevine DRM should work. See the relevant question for specific installation instructions.

Why are there URLs with the qjz9zk domain in them? Why use domain substitution?

qjz9zk is the common top-level domain name used by domain substitution. It is a relatively trivial way of disabling unwanted requests and notifying the user if any of these URLs attempt to connect without having to look through the many changes that happen to Chromium each version.

Does domain substitution break the HSTS preload list?

No, the list (which is located in net/http/transport_security_state_static.json) is explicitely excluded when generating the domain substitution list. In developer_utilities/, see the generate_domain_substitution_list() function for what files are excluded from domain substitution.

Why is Safe Browsing disabled?

See this Wikipedia article for info about Safe Browsing.

Safe Browsing communicates with Google servers in order to download the blacklists. If you are looking for a feature like Safe Browsing, I recommend uBlock Origin or uMatrix.

How do I install Flash player?

Adobe’s version of Flash player (as opposed to Google’s Flash player bundled with Chrome) on Windows and macOS has an auto-update feature. Linux users will have to install updates manually, or use a PPAPI Flash player package available from their distribution. The following instructions are for installing Adobe’s version of Flash player.

  1. Go to
  2. Select the target platform for running Flash in Step 1.
  3. For Step 2, select one of the following:
    • macOS: FP 23 Mac for Opera and Chromium - PPAPI (or the latest version)
    • Windows: FP 23 for Opera and Chromium - PPAPI (or the latest version)
    • Linux: FP 23.0 for other Linux 64-bit (.tar.gz) - PPAPI (or latest version and appropriate CPU architecture)
  4. Click the “Download now” button, then install.

There are also ways to get Google’s Flash player or other versions. See for more details.

How do I install Widevine CDM?

These instructions are platform-specific.

WARNING: For all platforms, it is recommended to download the Google Chrome version that has the same major version as ungoogled-chromium. Otherwise, there may be stability issues or crashes.


  1. Download the latest Google Chrome for Linux (.deb file)
  2. Inside data.tar.xz, extract ./opt/google/chrome/
  3. For installed packages, extract to /usr/lib/chromium, where all other Chromium files should be. For portable or custom-built versions, it should be placed alongside the other Chromium files. As of version 68, can also be placed under $HOME/.local/lib/.

As of version 67, has been deprecated, and the Debian package ungoogled-chromium-widevine no longer exists.




This applies to version 55.0.2883.95. In case you’re using a different version, make sure to edit the command accordingly.

  1. Download the latest Google Chrome for macOS (.dmg file)
  2. Put the downloaded Google and ungoogled-chromium’s in the same folder
  3. Run the following command in the Terminal:

cp -R Google\\ Chrome\ Framework.framework/Libraries/WidevineCdm\ Framework.framework/Libraries/

Note that there is no slash after WidevineCdm.

How do I get the Namespace Sandbox to work on Linux?

Enable the kernel option unprivileged_userns_clone

How to get FIDO U2F security keys to work in Google sign in?

Google sign in uses a specific extension to access the security key’s information. You’ll need to install this extension to make this function. After installation you might need to restart your computer to make it work.