When I write an email, the touch bar has a 'send' key, which I find is one of the useful features of the touch bar (I know I could also press command-shift-D, but a single key is often convenient). However, exactly this key is very unresponsive. I often have to press it multiple times. I don't have that issue with other 'keys' on the touch bar. Anyone else observed this? Since the touch bar is otherwise working, I guess it must be a software issue. But an odd one.