Before downloading the patch, you must switch your game version within the Steam Client :
: Steam will automatically begin a small download to update your game files to the 64-bit version. 2. Apply the GMod CEF Codec Fix
: Get the latest macOS version from the GModCEFCodecFix GitHub or use the simplified guide at Solstice Game Studios . Make Executable : Open your Terminal application. Type chmod +x (with a space at the end). Gmod Install Mac Direct
: In the "Beta Participation" dropdown, select x86-64 - Chromium + 64-bit Binaries .
To play GMod natively on macOS (including Intel and Apple Silicon like M1/M2/M3), you must use a specific 64-bit beta branch and a community-made patch. 1. Enable the 64-Bit Beta Branch Before downloading the patch, you must switch your
: Go to your Steam Library and right-click Garry's Mod . Open Properties : Select Properties > Betas .
Installing Garry’s Mod (GMod) on a Mac involves more than just a simple click of the "Install" button. While Steam lists it as Mac-compatible, Apple's removal of 32-bit application support means the default version of GMod will not launch on modern macOS versions. Make Executable : Open your Terminal application
: Double-click the file to open it. It will automatically patch your GMod installation files to support the modern macOS architecture. 3. Launching the Game