Pressing the ESC key while writing a message will delete the entire text instead of canceling the mentioning process.
Not a bug. But may be improved in case this makes sense for us to change it that way.
For beta 70 this will no longer happen. It will need a second ESC to cancel whole text
Awesome!
:,(
not found in patches
That’s a new bug 
It definitely was in beta 70 rc2.
xD I keep my fingers crossed