I have been noticing this for a wile that my Sketch-names get lost but never bothered to figure out why.
I today noticed the same behavior with groups and it seems to always happen after suppressing them.
I have 4 groups with each containing a sketches and emboss for a different text.
I usually have 3 groups suppressed (the ones not currently in use) and those have all (multiple times) lost their name in the past week.