Not catching right mouse click in firefox?

Question

JavaScript

firefox treats a right mouse click as a left click. The problem is this:
when you right-click on a shaded area while the popup window is open, it closes. This behavior is only in firefox, it works in others.

"contextmenu', function(){...} и 'mousedown', function(){if(event.which === 3){...}}

do not change the situation

Answer 1

jsfiddle.net/24hc05h9
when right clicking on a window in firefix it closes