Can't resize windows horizontally

[fnetX]

Reporter info

 * Distribution: Debian 9.1
 * Gtk+ 3.0 version: 3.22.11-1
 * Desktop environment: MATE 1.16.2
 * Pop version: Pulled from git and used ./install.sh (latest)

Actual issue
I cannot resize windows horizontally with the pop themes. Vertically is possible.
Works correctly with other Themes.

Steps to reproduce
Install Pop Theme and try to resize a window horizontally

Expected behavior
Resize Cursor appearing when at the border of the window. Moving when clicked resizes the window.

Behavior in Adwaita
Same behavior in Adwaita.

[isantop]

This sounds like a bug with MATE's window manager. It sounds like it doesn't correctly handle borderless windows. Unfortunately, this isn't within the scope of the theme to fix.