Cannot set Merge Distance for Remove Doubles

It’s crazy! Why can’t I see the Merge Distance attribute when I click Remove Doubles here? (I’ve attached the blend file)

If I just start a new blend file it works, but is there a setting here I don’t know about?cannot_set_merge_distance.blend (427 KB)

its hidden :wink:

OMG haha wth!!! thank you for making that GIF!!! I have NEVER seen that hidden before! Much appreciated!!!

Press F6 after clicking remove doubles