How to implement a function which add a click option for border when mouseover a flash?

Question

I want implement a function for my extension of Firefox. and when my mouse over a flash or other objects in a web,a border will show and around this flash, and up the border is a tab we can click it to invoke a App, just like Thunder extension , now I have implement showing a border around flash ,but How to add a tab on border to invoke a App,Thank you very much!