Thanks for the information provided to the Illustrator team.
We are able to reproduce this issue at our end and the engineering team is currently isolating this issue further to get to the root cause.
With Best Regards,
An error occurred while saving the commentAnonymous commented
I've been having this problem for a week and going out of my mind!. I'm using CC 17 and Sierra.
Turns out it was the virus software Webroot SecureAnywhere what was blocking a few keyboard functions. Checking the "pause secure keyboard entry" worked like a charm!