External UFO changes require two reloads

I have the same UFO file open in Metrics Machine and Glyphs. When I save in Metrics Machine I get the dialog in Glyphs asking me if I want to keep the Glyphs version or reload. If I click reload, it immediately presents the dialog again and I must reload a second time.

What is it, what you do in MM?

Metrics Machine does nothing but create and edit kerning groups and kerning pairs.