Well… I was just about to create a new topic for this, when this topic popped up at the top of the similar list. 
(And yes, education prompt, I do want to revive this topic which, IMO, has gotten too little love. 
)
Since this is apparently a big ask, I’m willing to narrow it down a little 
(Here’s what I had composed before I jumped back into this topic):
Wishlist: standardize Ctrl-Enter from a text box for submit
I can submit a post with Ctrl-Enter
I can submit an assignment from its comment box with Ctrl-EnterI cannot submit a user note with Ctrl-Enter
[I’m willing to bet there are more things that go in this list]
So let me renew my request for making UI features that look similar, work similarly.
Pretty please?