Make the obscurer window one pixel smaller from all sides.
Make the obscurer window one pixel smaller from all sides.

It's only meant as a fallback in case of compositor misbehavior, and
making it smaller adds compatibility with Cinnamon's compositor
(Muffin), which will then no longer unredirect in response to
xsecurelock starting.

google/xsecurelock,google/xsecurelock