SW 2016 surface face fillet Trim and attach option greyed out. why?

Could someone look at this and tell me if it's a bug or is my SW installation screwed up.

The option to Don't trim or attach is greyed out. I have to delete the feature and remake it to have the option accessible again.

Doesn't works the other way either if I start by not trimming and attaching. Is it a bug?

SolidworksSurfacing