Not saying this is necessarily a bug.
Could be a feature.

Just reporting that when I try to clone an entity that has a target (in this case the player) then the "c" key is stuffed into the Name box on the right.

I created a second trigger and I was able to clone it. At least right up to the time I gave it a target.

Regards,
Claude
p.s. This is totally easy to work around. Just mentioning it in case it is a symptom of an underlying thing-a-ma-jig that is more problematic.