Examine source code of Backnote

{
  "manifest_version": 2,
  "name": "Backnote",
  "description": "Copying text snippets made easy. Call a backnote on hotkeys, highlight text to copy and hover over to paste it.",
  "version": "1.61resigned1",
  "homepage_url": "https://polevoyd.com",
  "applications": {
    "gecko": {
      "id": "dmitry.polevoy@yahoo.com",
      "strict_min_version": "47.0a1"
    }
  },
  "icons": {
    "128": "images/icon.png"
  },
  "browser_action": {
    "default_icon": {
      "96": "images/icon.png"
    },
    "default_title": "Backnote"
  },
  "background": {
    "scripts": [
      "background.js",
      "edit-note.js"
    ]
  },
  "commands": {
    "backnote": {
      "suggested_key": {
        "default": "Ctrl+Shift+V"
      },
      "description": "Sending request to open a backnote tab"
    }
  },
  "options_ui": {
    "page": "options.html",
    "browser_style": true
  },
  "content_scripts": [
    {
      "matches": [
        "*://*/*"
      ],
      "js": [
        "content-script.js"
      ]
    }
  ],
  "permissions": [
    "tabs",
    "<all_urls>",
    "downloads"
  ]
}