diff --git a/proton b/proton
index 73d8a3ca..ab66b52a 100755
--- a/proton
+++ b/proton
@@ -1067,6 +1067,7 @@ def default_compat_config():
                 "24010", #Train Simulator
                 "374320", #DARK SOULS III
                 "65500", #Aura: Fate of the Ages
+                "4000", #Garry's Mod
                 ]:
             ret.add("gamedrive")