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Run Chromium with flags

There are command line flags (or "switches") that Chromium (and Chrome) accept in order to enable particular features or modify otherwise default functionality.

Current switches may be found at http://peter.sh/examples/?/chromium-switches.html


It is important to note that using these switches is not supported or recommended. They should only be used for temporary cases and may break in the future.

To use a command line switch:

On Windows:

  1. Right click on your "Chrome" icon.
  2. Choose properties
  3. At the end of your target line add the command line flag. For example:
    • --disable-gpu-vsync
  4. With that example flag, it should look like: chrome.exe --disable-gpu-vsync

On OS X:

/Applications/Chromium.app/Contents/MacOS/Chromium --remote-debugging-port=9222

# for Google Chrome you'll need to escape spaces like so:
/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --remote-debugging-port=9222

On Linux:

chromium-browser --remote-debugging-port=9222

Setting V8 Flags

V8 can take a number of flags as well, via Chrome's js-flags flag. For example, this traces V8 optimizations:
chrome.exe --js-flags="--trace-opt --trace-deopt --trace-bailout"

To get a listing of all possible V8 flags:
chrome.exe --js-flags="--help"

Browse the V8 wiki for more flags for V8.

Setting Flags for Chrome on Android

Visit 'about:version' to review the flags that are effective in the app. 

If you are running on a rooted device or using a debug build of Chromium, then you can set flags like so:

out/Default/bin/chrome_public_apk argv  # Show existing flags.
out/Default/bin/content_shell_apk argv --args='--foo --bar'  # Set new flags

You can also install, set flags, and launch with a single command:

out/Default/bin/chrome_public_apk run --args='--foo --bar'
out/Default/bin/content_shell_apk run  # Clears any existing flags

For production build on a non-rooted device, you need to enable "Enable command line on non-rooted devices" in about:flags, then set command line in /data/local/tmp/chrome-command-line, finally manually restart Chrome (restarting from about:flags page might no be enough to trigger reading this file).  See https://crbug.com/784947.

Setting flags for ContentShell on Android

There's an alternative method for setting flags with ContentShell that doesn't require building yourself:

1. Download a LKGR build of Android.
2. This will include both ChromePublic.apk and ContentShell.apk
3. Install ContentShell APK to your device.
4. Run this magic incantation

adb shell am start \
  -a android.intent.action.VIEW \
  -n org.chromium.content_shell_apk/.ContentShellActivity \
  --es activeUrl "http://chromium.org" \
  --esa commandLineArgs --show-paint-rects,--show-property-changed-rects

This will launch contentshell with the supplied flags. You can apply whatever commandLineArgs you want in that syntax.

Setting Flags for Chrome OS

  1. Put the device into dev mode, disable rootfs verification, and bring up a command prompt
  2. Modify /etc/chrome_dev.conf (read the comments in the file for more details)
  3. Restart the UI via:
    sudo restart ui
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