Examine source code of MLB TV Controls

{
  "manifest_version": 2,
  "name": "MLB TV Controls",
  "version": "1.2.2resigned1",
  "description": "Adds additional player controls to the MLB.tv player",
  "homepage_url": "https://github.com/patrickkenzie/mlb-tv-controls",
  "icons": {
    "48": "icons/icon.svg"
  },
  "applications": {
    "gecko": {
      "id": "mlbtvcontrols@patrickkenzie.com"
    }
  },
  "permissions": [
    "activeTab"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://*.mlb.com/tv/*"
      ],
      "css": [
        "controls.css"
      ],
      "js": [
        "content_scripts/controls.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "commands": {
    "skip_med": {
      "suggested_key": {
        "default": "Ctrl+Right"
      },
      "description": "Skip forward a medium amount"
    },
    "skip_long": {
      "suggested_key": {
        "default": "Ctrl+Shift+Right"
      },
      "description": "Skip forward a long amount"
    },
    "restart": {
      "suggested_key": {
        "default": "Ctrl+Shift+Left"
      },
      "description": "Jump to the beginning of the game"
    }
  },
  "web_accessible_resources": [
    "icons/*.png"
  ]
}