manifest.json

gistfile1.txt

{
    "manifest_version": 2,
    "name": "My Extension",
    "version": "1",
    "permissions": [
        "activeTab",
        "storage"
    ],
    "icons": {
        "128": "./icon.png"
    },
    "browser_action": {
        "default_icon": "./icon.png",
        "default_popup": "index.html"
    },
    "content_scripts": [
        {
            "matches": [
                "<all_urls>"
            ],
            "js": [
                "./content.js"
            ],
            "all_frames": true
        }
    ]
}