built-in slash commands now erase your message

The built-in slash commands such as /shrug have been ... questionably "improved" to now erase the message you had already typed before you went back to the beginning to add the /shrug. What gives?

Steps to reproduce:

1. Write a message

2. realize you want to add a /shrug emoji at the end

3. go back to the beginning of the message and type /shrug[space]

4. congratulations, your message is now gone and you have to start again.

Please ... Fix this.