Rich combo cannot execute command from click event

RIchCombo cannot call editor.execCommand from onClick function

I am working on a custom variables plugin. That is, a plugin to insert placeholders for a template.

I got it working from a single button. The button is assigned a command, which executes when the button is pressed.

However, I cannot seem to execute a command from a rich combo. The `RichCombo.onClick` function is called, but the `Command.exec` function is not called.

I would be very grateful for any answers you can provide.

Code for both plugins attached. The forums would not let me put the code inline, or attach JavaScript files.

Thanks.