Examine source code of Drive By Editor

{
  "name": "DriveByEditor",
  "description": "Allow user to proof web page",
  "version": "0.1.0.1resigned1",
  "manifest_version": 2,
  "icons": {
    "16": "icon16.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "contentScript.js"
      ]
    }
  ],
  "permissions": [
    "contextMenus",
    "clipboardWrite"
  ],
  "applications": {
    "gecko": {
      "id": "DriveByParser@dteviot.github.com"
    }
  },
  "minimum_chrome_version": "49",
  "minimum_firefox_version": "52"
}