A simple google search brought me to these two links:
What I hoped to find out is if this was an upstream extension or if this is just a hack. Either way, could someone tell me how to enable this mode on debian? (sid).
The best way is to compile from git with the patch.
Thanks for the link. I'm excited to hear that support is planned for 4.10, I will await a beta/testing release, I prefer not polluting my fs with stuff that I've compiled unless I cannot work at all.
Or you can use wmctrl, a cli app with which you can get full control over how you want to place your windows. Create keyboard shortcuts with wmctrl commands. It's much faster than having to drag the window to a certain position.