using window.addEventListener load once

Hi all,

I try to using load my jar once when user open firefox browser and end until
user close the browser .

So I'm using "window.addEventListener " to monitor the user action . but I
find when I close browser ,thar jar still working in background.

Have anybody knows what's happening ? or have someone meet the problem
before ?

Any tip ??

 

 

 

 

 

Galuschka