[FIX][UI/UX] User Administration with User Tracker: make popover not hide username link

There was a problem with the popover, while hovering the username link to user tracker the popover overlaped it, as explained on https://dev.tiki.org/item8000 and https://avan.tech/item71722-Admin-user-User-edit-link-is-not-accessible-when-user-tracker-is-used-and-has-tabs. The solution is to add some JS trickery so that the popover is to be displayed as it should be.