Chromium
Chromium is the open source version of Google's Chrome web browser. It features a minimal user interface, powerful web development tools, and a built in task manager. The Chromium Project is at the forefront of implementing new web standards.
Because Chromium is open source it is legally unable to include several features that the proprietary Google Chrome browser includes by default. Namely automatic updates. A complete list of the differences can be found in the chromium repository.
Installation
USE flags
USE flags for www-client/chromium Open-source version of Google Chrome web browser
X
|
Add support for X11 |
bindist
|
Flag to enable or disable options for prebuilt (GRP) packages (eg. due to licensing issues) |
cups
|
Add support for CUPS (Common Unix Printing System) |
custom-cflags
|
Build with user-specified CFLAGS (unsupported) |
debug
|
Enable DCHECK feature with severity configurable at runtime. Mostly intended for debugging and development, NOT RECOMMENDED for general use. |
ffmpeg-chromium
|
(binpkg only) Use Chromium FFmpeg fork (media-video/ffmpeg-chromium) rather than mainline FFmpeg (media-video/ffmpeg) |
gtk4
|
Build with GTK4 headers. |
hangouts
|
Enable support for Google Hangouts features such as screen sharing |
headless
|
Build Ozone only with headless backend, NOT RECOMMENDED for general use. |
kerberos
|
Add kerberos support |
libcxx
|
Use bundled libc++ instead of libstdc++ for building. |
lto
|
Build with Link Time Optimizations (via clang's ThinLTO) |
official
|
Enable Official build instead of Developer build. |
pax-kernel
|
Allow building on a PaX-enabled kernel |
pgo
|
Build with Profile Guided Optimizations (2-stage compilation) |
proprietary-codecs
|
Enable codecs for patent-encumbered audio and video formats. |
pulseaudio
|
Add sound server support via media-libs/libpulse (may be PulseAudio or PipeWire) |
qt5
|
Add support for the Qt 5 application and UI framework |
qt6
|
Add support for the Qt 6 application and UI framework |
screencast
|
Enable support for remote desktop and screen cast using PipeWire |
selinux
|
!!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur |
system-harfbuzz
|
Use system media-libs/harfbuzz instead of the bundled library. |
system-icu
|
Use system dev-libs/icu instead of the bundled one |
system-png
|
Use system media-libs/libpng instead of the bundled library |
system-toolchain
|
Use system toolchain instead of the bundled one (if possible) |
system-zstd
|
Use system app-arch/zstd instead of the bundled one. |
vaapi
|
Enable Video Acceleration API for hardware decoding |
wayland
|
Enable dev-libs/wayland backend |
widevine
|
Unsupported closed-source DRM capability (required by Netflix VOD) |
icu
To avoid an emerge slot conflict with dev-libs/libxml2, which prevents Chromium to be emerged,
icu USE flag must be set in /etc/portage/make.conf. If icu is newly set, update the system before emerging Chromium by issuing:root #emerge --ask --update --deep --newuse @worldL10N
There are many languages available via the L10N USE_EXPAND variable in Chromium. So many, in fact, that the wiki cannot display all of them. For a full list of localization languages run:
user $equery u www-client/chromium | grep -i l10nThe equery tools comes as part of the app-portage/gentoolkit package. It will need to be installed in order to use the above command.
For more information on localization see the Localization article.
Emerge
Be aware that compiling Chromium can take a significant amount of real time, CPU time, and system memory. Allow 2Gb of RAM per each make thread (as defined by MAKEOPTS, see this post). It is probably not a good idea to build Chromium when the system is under heavy load.
After setting USE flags as desired, emerge Chromium with the following command:
root #emerge --ask www-client/chromiumConfiguration
Clang
To build Chromium with Clang, first see Clang environments.
For Chromium specifically, the following env settings are needed:
/etc/portage/env/clang-chromium# Optionally, add these to EXTRA_GN:
# - thin_lto_enable_optimizations=true
# - use_thin_lto=true
# - is_cfi=true
EXTRA_GN="use_lld=true is_clang=true clang_use_chrome_plugins=false"
#
# Needed with GCC 11
CHROMIUM_FORCE_LIBCXX=yes
Then enable it (note that we take the base Clang config from the other article, then add the settings we just defined):
/etc/portage/package.env# compiler-clang: build with a general Clang environment (see Clang article)
# clang-chromium: build with tweaks specifically for Chromium
www-client/chromium compiler-clang clang-chromium
HiDPI
Chromium's visual output is generally disconnected from a Desktop environment's DPI scaling. It can be instructed to start in a scaled mode by using the --force-device-scale-factor command-line option. This option can be passed a integer or decimal value. Standard scaling begins at 1.0. For example, to make Chromium's UI 1.5x larger:
user $chromium --force-device-scale-factor=1.5A full list of command-line switches can be found here.
Native Wayland support
Since version 87, native Wayland support in Chromium can be enabled by passing the following options:
user $chromium --enable-features=UseOzonePlatform --ozone-platform=waylandTo set Chromium to start every time using the Wayland backend, append the following lines the user's Chromium configuration file:
~/.config/chromium-flags.conf--enable-features=UseOzonePlatform
--ozone-platform=wayland
Enable dark theme for pages (prefers-color-scheme)
Because of bug in May 2022 Chromium on GTK do not understand that user want to see dark pages. But you can set this preference manually:
/etc/chromium/defaultCHROMIUM_FLAGS="--force-dark-mode
--enable-features=WebUIDarkMode"
First is for regular pages, the second is for internal chrome:// pages.
Disable animations
To turn off animations, set the following parameters:
/etc/chromium/defaultCHROMIUM_FLAGS="--wm-window-animations-disabled
--animation-duration-scale=0"
Disable Tab Hover Cards
Since version 91.0.4472.77 it is no longer possible to disable the Tab Hover Cards within Chrome flags. There seems to be no priority at Google to add this feature back in. In order to disable them, you can add this patch to Portage:
/etc/portage/patches/www-client/chromium/hover-card.patchdiff --git a/chrome/browser/ui/views/tabs/tab_strip.cc b/chrome/browser/ui/views/tabs/tab_strip.cc
index 2c94eb0..1f7bde0 100644
--- a/chrome/browser/ui/views/tabs/tab_strip.cc
+++ b/chrome/browser/ui/views/tabs/tab_strip.cc
@@ -2149,6 +2149,7 @@ void TabStrip::OnMouseEventInTab(views::View* source,
}
void TabStrip::UpdateHoverCard(Tab* tab, HoverCardUpdateType update_type) {
+ return;
// Some operations (including e.g. starting a drag) can cause the tab focus
// to change at the same time as the tabstrip is starting to animate; the
// hover card should not be visible at this time.
See also Added setting for Tab Hover Cards.
Security
Policies
It is possible to set specific policies for chromium. This can be useful especially if the browser should be accessible by users, but the content should be restricted to trusted sites. It can also be configured to restrict the access to specified URIs, like the file:// protocol, to prevent users from surfing the file system.
Chromium looks in /etc/chromium/policies for existing policies. There are two types of policies which can be defined:
- managed
- recommended
Generally managed policies are maintained by an administrator and recommended policies are recommended for users but not required.
For further information about the two policy types the documentation should be referred on the Google Chrome support page.
The following example assumes managed policies. However, the procedure for recommended policies is very similar and can be found in the Chromium documentation.
Creating of managed policies
To set custom managed policies, a JSON file must be created in /etc/chromium/policies/managed/<filename>.json
It is important to ensure, that the
<filename>.json is not writable by non-admin users, to prevent overwriting of the policies by users, which would defeat the purpose of policies! The chown(1) and chmod(1) commands can be used to change ownership and rights if for any reason the file should be writable by non-admin users.The structure of the JSON file is the same for all chromium based browsers (Chrome, Chromium, Brave etc). An example JSON file could look like this:
{
"IncognitoModeAvailability": 1,
"URLBlocklist": [
"https://facebook.com",
"file://*",
"javascript://*",
"ftp://*",
"mailto:*"
],
"DefaultGeolocationSetting": 2,
"DefaultNotificationsSetting": 2,
}
This prevents the user from surfing on the file system using the file protocol, incognito mode, blocks the listed URIs and URLs, and the location and notifications. More settings, can be found in the policy list: https://www.chromium.org/administrators/policy-list-3/. If configured for other users as a service, it is recommended to block all sites at first and then define the allowed sites, to avoid abuse of the service. Please note that this only blocks the user from visiting specified locations. It does not disable the protocols on the system, so other applications must be configured separately.
If the policy was configured properly can be proofed on the special page: chrome://policy.
For a better structure, it is also possible to spread the policies over multiple JSON files. In this case it is indispensable to ensure that the same policy occurs only once per all files! If a policy is defined multiple times across the JSON files than the state of the policy will be undefined and it would be unclear which rule would be used!
Meaningful filenames and a simple grep across the files in case of doubt can help to prevent such misconfigurations.
Local certificates
Chromium (like many other web browsers, such as Firefox) does not use the system-wide CA certificate list.
To use a custom certificate when using Chromium-based Web browsers like Chrome, open chrome://settings/certificates, choose the "Authorities" tab, and import the certificate.
Usage
Chrome URLs
Much like Firefox, Chromium has many internal Chrome URLs (special pages) that are used for additional configuration, troubleshooting, task management, etc. An exhaustive list of special pages can be accessed by navigating to: chrome://about/
Prominent special pages include:
chrome://components/- Shows enabled components and provides a button to check for updates for each of them. It is sometimes necessary to manually update the PPAPI Adobe flash module via this interfaces when using Chrome.chrome://chrome/- Displays the About page which includes version information.chrome://extensions/- A page to manage extensions.chrome://flags/- Enable/disable experimental features.chrome://flash/- Displays special information about the Adobe Flash Player (if it is accessible by Chromium).chrome://gpu/- Displays information about use of graphics acceleration.chrome://history/- Displays web history. Also accessible through the sandwich menu or by pressing Ctrl+h.chrome://memory-redirect/- Measure the memory usage of the browser and per-tab usage.chrome://net-internals/- Lots of information on network connections.chrome://plugins/- Shows a list of plugins. Enable/disable them from this interface. (Deprecated in Chrome version 57[1].)chrome://version/- Displays more version information than thechromepage.
Troubleshooting
Screencast support
Screencast is disabled by default at runtime. Either enable it by navigating to chrome://flags/#enable-webrtc-pipewire-capturer inside Chromium or add --enable-features=WebRTCPipeWireCapturer as a value to the CHROMIUM_FLAGS variable in the /etc/chromium/default file.
Tabs crash
Occasionally tabs in Chromium crash. This can be caused by quite a few things, however one of the most common reason for occurrence is that the system is running low on memory. On Gentoo, this can especially happen if the system is compiling a www-client/chromium package update while running Chromium.
The free command can be used to see how much memory is available on the system:
user $free -htotal used free shared buff/cache available Mem: 15G 11G 735M 789M 3.4G 3.1G
The solution to is to free up memory until the large package compiles have finished. Open a resource monitor of choice and kill applications using large amounts of memory.