manifest.json

{
    "name":"ImageCatcher",
    "short_name":"ImgCatcher", 
    "version":"1.0",
    "description":"Download Images of an url",
    "permissions": ["storage","activeTab"],
    "background":{
        "scripts":["background.js"],
        "persistent":false
    },
   "content_scripts":[{
    "matches":["https://*/*","http://*/*"],
    "js":["jszip-utils.min.js","FileSaver.js","jszip.min.js","content.js"]
   }],
    "browser_action":{
        "default_popup":"popup.html",
        "default_icon":{
            "16":"images/ImgCatcher_16.png",
            "32":"images/ImgCatcher_32.png",
            "48":"images/ImgCatcher_64.png",
            "128":"images/ImgCatcher_128.png"
        }
    },
    "icons":{
        "16":"images/ImgCatcher_16.png",
        "32":"images/ImgCatcher_32.png",
        "48":"images/ImgCatcher_64.png",
        "128":"images/ImgCatcher_128.png"
    },
    "manifest_version":2
}