Creating a custom editor button to insert text

[Emmy2]

I wonder if someone can help me with this.

I want to create a new button on the regular and quickreply editors that will insert some pre-defined text into the reply box when it is clicked.

I am aware of this thread that will add extra buttons to the quickreply but those are for features already available on the full reply (like align, font etc.).

What I want to do is create a button for a CUSTOM function that is not anywhere else and that is NOT a custom bbcode.

In other words, a user clicks the button and a phrase like "abcdefghijk" is automatically inserted into the reply box so they don't have to type it themselves. Simply that.

Can this be done?

If it can, a little more complex would be if there was a drop-down menu to choose from several different phrases to insert....but that's not absolutely necessary...getting just the one custom phrase insert would be a tremendous help. I'm not a coder but I can follow directions. Can anyone help me? Thanks so much.