diff --git a/lutris/runners/wine.py b/lutris/runners/wine.py
index a98dcfd431..20480a796e 100644
--- a/lutris/runners/wine.py
+++ b/lutris/runners/wine.py
@@ -1088,7 +1088,8 @@ def get_env(self, os_env=False, disable_runtime=False):
 
         # Proton support
         if wine_config_version and "Proton" in wine_config_version and "lutris" not in wine_config_version:
-            env["GAMEID"] = "ULWGL-foo"
+            if not ("GAMEID" in env):
+                env["GAMEID"] = "ULWGL-foo"
             env["PROTONPATH"] = wine_exe[:wine_exe.index("files/bin")]
         return env