Filter for JSLink Column not working

Hi Experts.

I have a Column (Single line of text) in a Library which I use to calculate costs on Contracts. I have implemented this with a jslink which is working fine.

Now if I open the Filter-Selector there is just one Checkbox (Empty). I would have expected to see my values.

Is this By-Design? - Does Filtering do not work on JSLink-Columns?

Or am I missing something?

With kind Regards, Ronny