[Frosty Crunch]

I had a project with all the remaining actions colored gray. There were no blocking or date issues to explain it. I then displayed all actions, revealing a completed action before the first remaining action. I moved the completed action to the bottom of the sequence, which turned the first remaining action purple. I then moved the completed action back up to position 1. The first remaining action remained purple, as it should be.

Is this a bug, or is there some other explanation?