Show only leading and trailing whitespace

Can an option be added to show only leading and trailing whitespace and not for any whitespace in the middle of text?

You can already do this, but it's a bit hidden:

gsettings set org.xfce.mousepad.preferences.view.show-whitespace inside false

You can also adjust leading and trailing this way (instead of inside).

We didn't put all the possibilities in the preferences dialog so as not to overload it. Maybe it could be improved or better documented, let's leave this open.

added 2. Enhancement 7. Documentation labels