When I create a widget then it shows up in the add new widget for layer as

My Maps Record

How can I get rid of the Record part and make that Widget? Is there some setting I forgot? The documentation doesn't really show how to do this or at least I didn't find it if it exists.

This looks like the display name, which can be changed in the content type editor.

Indeed. But how can I make it so that it already has this particular string Widget in the name instead of Record? Does this get autonamed taken from the Model class?

I think "Record" is just part of your display name.

Ok, in that case how come that certain "Record"s have the Widget name directly shown in the layers overview? Html widget or menu Widget for example.

I don't know: I've never seen that. Are you sure you didn't put it there yourself?