Examine source code of Night Shift (Lux control)

{
  "manifest_version": 2,
  "version": "0.1.1resigned1",
  "name": "Night Shift (Lux control)",
  "description": "Control red, green, and blue color levels for both daytime and nighttime",
  "icons": {
    "16": "data/icons/16.png",
    "32": "data/icons/32.png",
    "48": "data/icons/48.png",
    "64": "data/icons/64.png",
    "128": "data/icons/128.png"
  },
  "permissions": [
    "tabs",
    "webNavigation",
    "storage",
    "alarms",
    "idle",
    "<all_urls>"
  ],
  "homepage_url": "http://add0n.com/eye-protector.html?from=night-shift",
  "background": {
    "persistent": false,
    "scripts": [
      "webext.js",
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": {
      "16": "data/icons/16.png",
      "32": "data/icons/32.png",
      "48": "data/icons/48.png",
      "64": "data/icons/64.png"
    },
    "default_popup": "data/popup/index.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{dc92027c-5b78-4f54-af39-f7c96a7bc8ca}"
    }
  }
}