Editing a message to contain nothing should delete the message

[TR-SLimey]

Is your suggestion related to a problem? Please describe.
I often find it much quicker to press ArrowUp + CTRL+A + Backspace + Enter than to move my mouse all the way to the delete button on a message, so I was disappointed to find out that Element actually changes its behaviour from send to insert new line when the edit field is empty. This is kind of confusing (the behaviour shouldn't change at least), but also could be used better.

Describe the solution you'd like
Since editing a message to be empty is basically an attempt at redacting it, Element should automatically redact any message which is edited to be empty. There could still be a confirmation box as is shown when redacting a message in the usual way, with confirm focused by default, in order to ensure that this is not done accidentally by pressing enter while re-writing a message. I think this would not only be quicker but also make Element more usable with just a keyboard.

Describe alternatives you've considered
None really. There could be (already is?) a dedicated shortcut, but that's another shortcut to memorise, over something quite intuitive imo.

[t3chguy]

Duplicate of #11024