How to toggle admin menu in Elgg Theme 5

Elgg Theme plugin: es.wzm.me/prod...
Feature: Ability to replace old admin menu in
We respect all Elgg contributors (github.com/Elg...) for great efforts these years, but we didn't like what they did with the admin topbar (sidebar early) in #Elgg 5.
Our developers offered the ability to use the old school admin sidebar or the new admin topbar as feature.
Here's how to do it using switch on/off button.