Created attachment 7296 
Screenshot before the breaking commit

After testing the current git version of xfwm4, I've noticed that the xfce4-terminal is missing black (semi-transparent) background near screen edges when maximized. I'll attach a screenshot 'before' and 'after' to explain best what I mean.

I've been able to bisect this down to the following commit:

commit aee8b25a522d84e2453ed4049a018ca17a6b9525
Author: Marcel Partap <mpartap@gmx.net>
Date:   Sun May 7 11:36:14 2017

    Do not prevent ALT+Mouse resizing for borderless maximized windows.


$ ./src/xfwm4 --version
	This is xfwm4 version 4.13.0git.b9f910bd (revision b9f910bd) for Xfce 4.12
	Released under the terms of the GNU General Public License.
	Compiled against GTK+-2.24.31, using GTK+-2.24.31.

	Build configuration and supported features:
	- Startup notification support:                 Yes
	- XSync support:                                Yes
	- Render support:                               Yes
	- Xrandr support:                               Yes
	- Xpresent support:                             No
	- Embedded compositor:                          Yes
	- Epoxy support:                                Yes
	- KDE systray proxy (deprecated):               No