Examine source code of Tabsmack

{
  "name": "Tabsmack",
  "description": "Smack the active tab and move it to the beginning or end of the tab list.",
  "homepage_url": "https://github.com/nbp/tabsmack/",
  "manifest_version": 2,
  "version": "0.6.1resigned1",
  "author": "Nicolas B. Pierron",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "tabs"
  ],
  "commands": {
    "move-to-front": {
      "suggested_key": {
        "default": "Ctrl+Shift+Home"
      },
      "description": "Send the active tab to front of the list of tabs."
    },
    "move-to-back": {
      "suggested_key": {
        "default": "Ctrl+Shift+End"
      },
      "description": "Send the active tab to back of the list of tabs."
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{59407af3-d200-4c2d-9b6e-ae0a7ecd231c}"
    }
  }
}