filter environments before launch

app_launcher.py

@@ -29,16 +29,9 @@ def main(input_json_path):
         data = json.load(stream)
 
     # Change environment variables
-    # - environments that are in current environments and are not data are
-    #   removed
-    if "env" in data:
-        env = data["env"]
-        # Pop environment variable keys that are not in source
-        for key in set(os.environ.keys()) - set(env.keys()):
-            os.environ.pop(key)
-
-        for key, value in env.items():
-            os.environ[key] = value
+    env = data.get("env") or {}
+    for key, value in env.items():
+        os.environ[key] = value
 
     # Prepare launch arguments
     args = data["args"]

openpype/hosts/nuke/__init__.py

@@ -18,13 +18,7 @@ def add_implementation_envs(env, _app):
             new_nuke_paths.append(norm_path)
 
     env["NUKE_PATH"] = os.pathsep.join(new_nuke_paths)
-    # NOTE: Poping of the key is right way. But is commented because there is
-    #   a bug in `app_launcher.py` which only change values and not remove
-    #   existing.
-    # Fixed with https://github.com/pypeclub/OpenPype/pull/2655
-    #   but this fix requires new build
-    # env.pop("QT_AUTO_SCREEN_SCALE_FACTOR", None)
-    env["QT_AUTO_SCREEN_SCALE_FACTOR"] = ""
+    env.pop("QT_AUTO_SCREEN_SCALE_FACTOR", None)
 
     # Try to add QuickTime to PATH
     quick_time_path = "C:/Program Files (x86)/QuickTime/QTSystem"

openpype/lib/applications.py

@@ -1040,10 +1040,19 @@ class ApplicationLaunchContext:
         # Prepare data that will be passed to midprocess
         # - store arguments to a json and pass path to json as last argument
         # - pass environments to set
+        app_env = self.kwargs.pop("env", {})
         json_data = {
             "args": self.launch_args,
-            "env": self.kwargs.pop("env", {})
+            "env": app_env
         }
+        if app_env:
+            # Filter environments of subprocess
+            self.kwargs["env"] = {
+                key: value
+                for key, value in os.environ.items()
+                if key in app_env
+            }
+
         # Create temp file
         json_temp = tempfile.NamedTemporaryFile(
             mode="w", prefix="op_app_args", suffix=".json", delete=False