src/app/components/create-room/utils.ts

@@ -139,8 +139,11 @@ export const createRoom = async (mx: MatrixClient, data: CreateRoomData): Promis
       data.allowFederation,
       data.additionalCreators,
     ),
-    power_level_content_override:
+    // [Gitea #328] Every non-space room gets call.member at user level, not just
-      data.type === RoomType.Call ? createVoiceRoomPowerLevelsOverride() : undefined,
+    // voice rooms: the call button is shown in private group rooms too, and with
+    // Synapse's state_default (50) only admins could start or join a call there
+    // ("You don't have permission to join!").
+    power_level_content_override: createVoiceRoomPowerLevelsOverride(),
     initial_state: initialState,
   };