Mirroring windows position in taskbar

[plucafs]

Hi! Thank you for karousel first thing first.

I want to ask about a behaviour that I cannot reproduce.
In the readme's video, the position and column stacking order of the windows is mirrored in the taskbar.
I achieved a similar effect with the "Icons-Only task manager" widget, setting inside the "Behaviour" section, tha property "Sort" to "By horizontal window position". But I can't mirror the windows stacking. How is it achievable?

Thanks!

[AndydeCleyre]

That recording was made using an unfinished custom applet by the Karousel developer, not a standard task manager.