Block autocomplete problem

Not sure if it is the plugin's problem.

1. Type blk
2. Press `tab`, see this:
    ```twig  
    {% block | %}
    
    {% endblock %}
    ```
3. Start typing the existing block's title
4. Press `tab` to autocomplete
5. See this:
    ```twig
    {% block title
    
    {% endblock %}
    ```

So, `%}` disappears after pressing `tab`.