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User is not able to use the Create Comment shortcut (C by default) to create a comment in either the Behavior Tree or EQS editor graphs.
This works in blueprint graphs and makes adding comments easier, so it would be good to have them in these graphs as well.
RESULT:
Comment is not created.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-37797 in the post.