improving ux: expanding rich text editor

### Your use case

#### What would you like to do?

Expand the rich text editor in an easier way
#### Why would you like to do it?
Its currently bad ux: you can slide from inside the input field, but NOT from the handle that is indicating this funciunality?!
#### How would you like to achieve it?

Exchange it for an button with - way flatter, but simmilar to "^" - arrow shape. (Maybe move it to one side)

### Have you considered any alternatives?

Make the "handle" easyer to hit.

### Are you willing to provide a PR?
No