Electron Media Patch

Version-specific Electron/Chromium patches for enabling additional media codec support, including:

• HEVC / H.265
• AC3
• E-AC3
• AC4
• DTS
• Dolby Vision-related platform flags

These patches are intended for building custom Electron binaries.

Caution

These patches only modify source/build behavior. They do not grant any codec, patent, distribution, or platform licenses. Make sure you understand the legal/licensing requirements before distributing binaries with proprietary codec support.

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Supported versions

• v42.4.0
• v36.2.1+

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Prerequisites

Source: Electron GN build instructions

All platforms

Install:

• Git
• Python 3
• Node.js
• Yarn/Corepack
• depot_tools
• Ninja / autoninja
• A C/C++ toolchain for your platform

Install depot_tools separately, outside the Chromium checkout:

git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git depot_tools

Add it to your PATH.

On macOS/Linux:

export PATH="$PWD/depot_tools:$PATH"

On Windows cmd:

set PATH=C:\src\electron\depot_tools;%PATH%

Important

On Windows, use a standalone depot_tools checkout. Do not rely on src\third_party\depot_tools as your user-facing depot_tools install. The vendored checkout can be incomplete for command-line use.

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Windows-specific prerequisites

Install:

• Visual Studio 2022 Build Tools
• Desktop development with C++
• Windows 10/11 SDK
• Debugging Tools for Windows

The Debugging Tools are required because Chromium expects:

C:\Program Files (x86)\Windows Kits\10\Debuggers\x64\dbghelp.dll

Set:

set DEPOT_TOOLS_WIN_TOOLCHAIN=0

This tells Chromium/depot_tools to use your locally installed Visual Studio instead of trying to use Google’s internal toolchain.

If Python resolves to the Microsoft Store alias, disable:

Settings -> Apps -> Advanced app settings -> App execution aliases

Turn off:

python.exe
python3.exe

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Linux-specific prerequisites

From the Chromium source root after sync:

cd /home/$USER/src/electron/src
sudo ./build/install-build-deps.sh --no-prompt

If using @electron/build-tools, install Node through a version manager such as nvm. Do not install @electron/build-tools with sudo.

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Getting the source

Example checkout path:

~/src/electron

On Windows, use something short like:

C:\src\electron

macOS/Linux

Run from the directory where you want the checkout:

mkdir -p ~/src/electron
cd ~/src/electron

gclient config --name "src/electron" --unmanaged https://github.com/electron/electron
gclient sync --with_branch_heads --with_tags

Windows

Run from cmd or x64 Native Tools Command Prompt:

mkdir C:\src\electron
cd /d C:\src\electron

gclient config --name "src/electron" --unmanaged https://github.com/electron/electron
gclient sync --with_branch_heads --with_tags

This will take a while.

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Check out the target Electron version

Run from:

<checkout>/src/electron

Example for v42.4.0:

cd src/electron
git fetch origin --tags
git checkout v42.4.0
git describe --tags --exact-match

Expected output:

v42.4.0

Then re-sync dependencies for that tag.

Run from:

<checkout>

cd ../..
gclient sync --with_branch_heads --with_tags -f

Important

Do not apply patches to main unless the patches were made for main. Most patch failures happen because the Electron tag does not match the patch version.

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Apply patches

Copy the patch files into:

<checkout>/patches

Example:

~/src/electron/patches

or on Windows:

C:\src\electron\patches

Run from the Chromium source root:

<checkout>/src

macOS/Linux

cd ~/src/electron/src

for p in ../patches/electron-v42.4.0-*.patch; do
  echo "Checking $p"
  git apply --check "$p" || exit 1
done

for p in ../patches/electron-v42.4.0-*.patch; do
  echo "Applying $p"
  git apply "$p" || exit 1
done

Windows cmd

Run from:

C:\src\electron\src

cd /d C:\src\electron\src

for %p in (..\patches\electron-v42.4.0-*.patch) do git apply --check "%p"
for %p in (..\patches\electron-v42.4.0-*.patch) do git apply "%p"

If running inside a .bat file, use %%p instead of %p.

Verify:

git status --short
git diff --check

git diff --check should ideally print nothing.

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Check whether patches are already applied

From:

<checkout>/src

for p in ../patches/electron-v42.4.0-*.patch; do
  echo ""
  echo "Patch: $p"

  if git apply --reverse --check "$p" >/dev/null 2>&1; then
    echo "already applied"
  elif git apply --check "$p" >/dev/null 2>&1; then
    echo "not applied"
  else
    echo "not cleanly applicable; possibly partially applied or wrong Electron version"
  fi
done

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Required GN args

These builds require proprietary codec flags.

Base args:

import("//electron/build/args/release.gn")
target_cpu="x64"

proprietary_codecs=true
ffmpeg_branding="Chrome"

enable_platform_ac3_eac3_audio=true
enable_platform_ac4_audio=true
enable_platform_dts_audio=true
enable_platform_dolby_vision=true
enable_platform_hevc=true
enable_hevc_parser_and_hw_decoder=true

use_remoteexec=false
use_reclient=false
use_siso=false

For v42.4.0, adding this may be necessary to avoid version detection failures during generated TypeScript/API steps:

override_electron_version="42.4.0"

If a GN arg is unknown for your target Electron/Chromium version, remove that arg or update the patch set for that version.

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Generate build files

Run from:

<checkout>/src

macOS/Linux

gn gen out/Release-x64 --args='import("//electron/build/args/release.gn") target_cpu="x64" proprietary_codecs=true ffmpeg_branding="Chrome" enable_platform_ac3_eac3_audio=true enable_platform_ac4_audio=true enable_platform_dts_audio=true enable_platform_dolby_vision=true enable_platform_hevc=true enable_hevc_parser_and_hw_decoder=true use_remoteexec=false use_reclient=false use_siso=false override_electron_version="42.4.0"'

For Linux, you can use a Linux-specific output directory:

gn gen out/Release-linux-x64 --args='import("//electron/build/args/release.gn") target_os="linux" target_cpu="x64" proprietary_codecs=true ffmpeg_branding="Chrome" enable_platform_ac3_eac3_audio=true enable_platform_ac4_audio=true enable_platform_dts_audio=true enable_platform_dolby_vision=true enable_platform_hevc=true enable_hevc_parser_and_hw_decoder=true use_remoteexec=false use_reclient=false use_siso=false override_electron_version="42.4.0"'

Windows cmd

Run from:

C:\src\electron\src

gn gen out\Release-win-x64 --args="import(\"//electron/build/args/release.gn\") target_os=\"win\" target_cpu=\"x64\" proprietary_codecs=true ffmpeg_branding=\"Chrome\" enable_platform_ac3_eac3_audio=true enable_platform_ac4_audio=true enable_platform_dts_audio=true enable_platform_dolby_vision=true enable_platform_hevc=true enable_hevc_parser_and_hw_decoder=true use_remoteexec=false use_reclient=false use_siso=false override_electron_version=\"42.4.0\""

If gn is not found on Windows, make sure standalone depot_tools is first in PATH.

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Build ffmpeg first

Build ffmpeg before the full Electron target. This catches codec patch issues early.

Run from:

<checkout>/src

macOS/Linux

autoninja -C out/Release-linux-x64 third_party/ffmpeg:ffmpeg

or, if you used out/Release-x64:

autoninja -C out/Release-x64 third_party/ffmpeg:ffmpeg

Windows

Run from:

C:\src\electron\src

autoninja -C out\Release-win-x64 third_party/ffmpeg:ffmpeg

If autoninja is unavailable, use ninja directly:

ninja -C out/Release-linux-x64 third_party/ffmpeg:ffmpeg

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Build Electron

Run from:

<checkout>/src

macOS/Linux

autoninja -C out/Release-linux-x64 electron electron:electron_dist_zip

or:

autoninja -C out/Release-x64 electron electron:electron_dist_zip

Windows

Run from:

C:\src\electron\src

autoninja -C out\Release-win-x64 electron electron:electron_dist_zip

The final link step can take a long time, especially on Windows. It may appear quiet while linking electron.exe and generating .pdb files.

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Packaging output

The distributable zip is produced by:

electron:electron_dist_zip

Search for artifacts:

macOS/Linux

find out -maxdepth 3 -name "*.zip" -o -name "dist*"

Windows

dir out\Release-win-x64\*.zip
dir out\Release-win-x64\dist*

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Linux stripping

On Linux, if needed, strip debug/symbol information before packaging:

cd <checkout>/src
electron/script/strip-binaries.py -d out/Release-linux-x64

Then build the dist zip:

autoninja -C out/Release-linux-x64 electron:electron_dist_zip

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Troubleshooting

Patch fails to apply

Most common causes:

• Wrong Electron tag
• gclient sync was not rerun after checking out the tag
• Patch set is incomplete
• Patch was already partially applied

Check:

cd <checkout>/src/electron
git describe --tags --exact-match

Then rerun from:

<checkout>

gclient sync --with_branch_heads --with_tags -f

Build asks for RBE/reclient authentication

You are trying to use remote build settings. Disable them:

use_remoteexec=false
use_reclient=false
use_siso=false

If using @electron/build-tools, also set:

"remoteBuild": "none"

Windows: python3_bin_reldir.txt not found

You are probably using vendored depot_tools from:

src\third_party\depot_tools

Use a standalone depot_tools checkout instead:

C:\src\electron\depot_tools

and put it first in PATH.

Windows: dbghelp.dll not found

Install Debugging Tools for Windows through the Windows SDK installer.

Verify:

dir "C:\Program Files (x86)\Windows Kits\10\Debuggers\x64\dbghelp.dll"

Windows: Failed to get git tag

Add:

override_electron_version="42.4.0"

to your GN args.

Also verify:

cd /d C:\src\electron\src\electron
git describe --tags --exact-match

electron_dist_zip missing

You probably built only:

electron

Build the dist target too:

autoninja -C out/Release-linux-x64 electron:electron_dist_zip

or build both at once:

autoninja -C out/Release-linux-x64 electron electron:electron_dist_zip