I did find yesterday that in the newest version the bottom right didn't work anymore for the mini bar. It appears that depending on model and koreader version the gestures are rather different.
Thanks for pointing out how to re-enable this feature.
EDIT: With the latest version the mini bar toggle is indeed at the lower middle for the Glo. (Cracked the screen of my H2O.

)However, I couldn’t find the option to in gesture manager. No bar mentioned at all.