A transparent jpeg? Never seen that.
But neither than less. We do not have any power over what the Browser does from your clipboard to the insert. If it decides that transparent backgrounds suck (don’t get me wrong 
) we won’t have much power on that.
So at that point I’m afraid you can’t do anything.
The backend editor and frontend one are actually exact the same already.
Please understand that I can’t and won’t forecast possible functions of the future and the way they might work.
We in general do not communicate ETAs. Not for issue fixes nor releases.