Examine source code of Context Wikipedia

{
  "manifest_version": 2,
  "name": "Context Wikipedia",
  "version": "1.0",
  "description": "Select word, right click: Search for page on Wikipedia. A simple WebExtension that provides a context menu entry to look up selected word on the English Wikipeida. Opens results in a new tab next to the current one.",
  "icons": {
    "48": "icons/icon.svg"
  },
  "applications": {
    "gecko": {
      "id": "context-wikipedia@addons.mozilla.org",
      "strict_min_version": "45.0"
    }
  },
  "permissions": [
    "contextMenus"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  }
}