How to add a custom right-click menu to a webpage?

Question

I want to add a custom right-click menu to my web application. Can this be done without using any pre-built libraries? If so, how to display a simple custom right-click menu

Answer 1

You should remember if you want to use the Firefox only solution, if you want to add it to the whole document you should add contextmenu="mymenu" to the tag not to the body tag.
You should pay attention to this.