Has anyone else ever seen this before??

I've been emailing back and forth with a prospect and just got this as a response.

Am I super behind on this feature? Or is this something new that no one told me about? OR did he simply just type out "xyz liked your email"?

I feel more confused than I should be lol end of quarter is melting my brain

Additional question, is it appropriate to respond after that? We were talking about different competitors and I had just sent him a list of who the main ones are & this was his response.