I also want to contribute Mozilla community.
My browser extension work like shimeji extension for chrome but i can’t find it source and also find one on:- https://github.com/TigerHix/shimeji-ee but don’t know much java to understand & write code.
So I am asking for your help on how can i implement my idea, means what api or example code should use for overlays image object on screen. I see some popup implementation but it remain join with extension menu button.
I see some https://github.com/mdn/webextensions-examples/ but not able to find similarity in my idea.
My initial effort is here
please provide little guidance!