diff --git a/level_editor/editor.lua b/level_editor/editor.lua
index fac3a00..813a5f0 100644
--- a/level_editor/editor.lua
+++ b/level_editor/editor.lua
@@ -480,6 +480,11 @@ local function saveRoomFromEditor()
 		removeFromSource("rooms/" .. oldName .. ".sav")
 		gameWorld:renameRoom(oldName, name)
 	end
+	-- The project source is now authoritative. Drop any runtime copy so it
+	-- cannot shadow this editor save the next time the game starts.
+	clearRuntimeSaveData(name)
+	if oldName and oldName ~= name then clearRuntimeSaveData(oldName) end
+	suppressRuntimeAutosave = true
 	gameWorld:invalidatePreview(name)
 	if editorView == "world" then rebuildWorldRoomButtons() end
 	currentRoom.name = name
@@ -506,6 +511,7 @@ local function clearRuntimeSaves()
 	end
 
 	local removed = clearRuntimeSaveData(clearAll and nil or roomName)
+	suppressRuntimeAutosave = true
 	clearSaveConfirmationExpires = 0
 	clearSaveConfirmationScope = nil
 	if roomName then
diff --git a/main.lua b/main.lua
index fbc5c3c..fb876d9 100644
--- a/main.lua
+++ b/main.lua
@@ -55,7 +55,9 @@ end
 -- Autosave on close so a position reached by moving within a room (short of a
 -- room-to-room transition, which already autosaves in nextRoom) survives.
 function love.quit()
-	if currentRoom then
+	-- An explicit editor save/clear removes the runtime copy intentionally;
+	-- don't immediately recreate it while shutting down.
+	if currentRoom and not suppressRuntimeAutosave then
 		currentRoom:save()
 		if gameWorld then gameWorld:setLastRoom(currentRoom.name) end
 	end