Unable to change new layer name

An annoyance.
While working seems to happen that when creating a new layer, I can not change its name.
This can be corrected by saving model. And after that, the layer can be named.
It seems (by memory, not systematically exploring this) that if I have not saved the model for some times, this annoyance returns.

Hi -
Please run the Rhino SystemInfo command and copy-paste the result here.
-wim