JEM Groups permission and categorization

Perhaps it would be good to give an error notice when you try to post in a category, where you have no rights.
Now you only can't save and if it's the only chosen category, you get the info, that you must choose a category.

Hi Jojo,

maybe I misunderstand but you can't post in a category where you have no rights. You have not choosen a category so you must do that. Please take a look:

The first entry was clicked but is not selectable. If you click into another field (or the Save button) the dotted frame around "internal Events" will be away so there is absolutely no difference between clicking a disabled category or never clicking anything.

Trick: press the down arrow key on your keyboard and you will have the first category allowed selected. Now you will not be able to not select a category.

Yes, I know. But your picture is really good (for others too).
I remember in an ealier phase, the not selectable categories were hidden. With that knowledge I first thought, now it's possible to select each category.
But I am learning. I think, it's ok so!