Popup Menu in XBar Addon Managemeant
In popup, you can use Left/Right-Click.
You can add any function you need in popup menu, like toggle your addon, open GUI...
There is a tooltip for your addon, you can add any information which you want, like author, usage, description...
One Page Sample - GUI
You can also use UICommonFrameTemplate or other backdrops.
Two Pages Sample - GUI
There are 3 levels for page in XBar Addon Management list.