[Case 1080657] GenericMenu doesn't show shortcuts - By purpose?

Hi,
I'm testing my editor extension against the Untiy 2018.3b01 beta version and I noticed that all my GenericMenus don't show shortcuts while the Unity internal ones do:


(Left is my editor extension; Right is Unity's Menu Bar)

I did some searching but found no explanation if this is a bug or by design (probably related to the new shortcut window currently in preview)? If by design, how can we show this "shortcut texts" in our custom menus again?

Thank you very much.

Edit: Just noticed that this problem also appears in the context menu's of Unity Timeline so I assume this is a bug --> reported (case 1080657).