Feature parity between comment editing and private message text entries

[RocketRide9]

Is your feature request related to a problem? Please describe.
Currently there is only a text entry while writing private messages and no way to upload image or preview a message.

Describe the solution you'd like
Make private message text entry equal in features with comment entry

Describe alternatives you've considered
I filled it because I can't send an image to a bot via private messages. So ability to attach images would be already very good.

Additional context
comments versus private messages