Examine source code of Tab Tools

{
  "manifest_version": 2,
  "name": "Tab Tools",
  "version": "1.0.7",
  "author": "Nils Maier",
  "homepage_url": "https://github.com/nmaier/tabtools",
  "description": "Helps you manage your tabs a little bit",
  "icons": {
    "32": "icon.svg",
    "48": "icon.svg",
    "64": "icon.svg",
    "128": "icon.svg"
  },
  "permissions": [
    "tabs",
    "menus"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "applications": {
    "gecko": {
      "id": "tabtools@tn123.org"
    }
  }
}