First occurred: two weeks; after using the SD-Card as integrated memory. The widget worked well after that. I deletet the widget accidentaly and could not get it back since then.
It’s weird that they completely hide the widgets when there are shortcuts. Try long-pressing empty space on the home screen. That usually also shows a list of widgets.
Maybe the list is sorted in a strange way - did you check the whole list? I don’t know what could be causing this. Maybe someone else who has the same device knows more.
Its not in the list. I checked the hole list. The problem occured after I changed the memory settings from the SD Card to integrated memory. But I have no Idea, how this could cause this problem.