My first chameleon would open his mouth when I opened mine, but I don't think he was really mimicking me. He probably thought I was about to eat him and was getting ready to put up a fight.
Ok well I let my chameleon play on his free range after I got off work, he would always be staring at me while he was climbing around and well I passed out for like an hour and when I woke up I saw him sleeping, idk since he saw me sleeping and obviously I wasn't moving so he went to sleep to?? But I woke him up and put him back in his cage. I watched him eat and drink water and now he is just basking. Extremely odd?:/
Not exactly mimicing but my girl will move with me ie. I'm looking at her and if I move to one side she will move to still be looking at me. I have fun with that one for hours
Sleeping is not good though, keep an eye on him for sure.