Markdown editor toolbox

Hi there,

I’m looking for a way to extend the default markdown editor with a toolbox.
There are contributors (Reporters) who are only testing the application, and while the md syntax is fairly simple, they have problems using it.

I’m not familiar with ruby, so I though of using a 3rd party library like

(GitLab CE, 7.14.3)

Any advice is welcome, cheers!