Use the backup to solve the residual after deleting the code.

app/src/main/java/org/autojs/autojs/ui/edit/EditorView.java

@@ -427,6 +427,8 @@ public class EditorView extends FrameLayout implements CodeCompletionBar.OnHintC
     }
 
     public Observable<String> save() {
+        String path = mUri.getPath();
+        PFiles.move(path, path + ".bak");
         return Observable.just(mEditor.getText())
                 .observeOn(Schedulers.io())
                 .doOnNext(s -> PFiles.write(getContext().getContentResolver().openOutputStream(mUri), s))