"Surround with" swallows previous tags.

I created a custom "surround with" with the following syntax: {% trans "$SELECTION$" %}

if I now apply this to the following code (Only "Upgrade" is selected): {% block title %}Upgrade{% endblock %}

It results in {% trans "Upgrade" %}{% endblock %}. The opening {% block title %} gets removed, although it was not selected.

This doesn't happen if the there is eg. a html tag in front of the string.