With the middle mouse click I configured some croparia fruit to min=0 max=0 and void.
Works! Yay. No more fruit from tall grass.

How can I change this back?

mmh..
that's tricky. I never thought about this.
maybe you shouldn't have done that.
I'll think of something

Maybe a new panel in the config where only the names of such doomed items/blocks are listed? With a reset button at each name?

Now I know I shouldn't have done this. But it is possible and gave me a very good feeling as it worked perfectly as intended.