Examine source code of CommPeak - PBX Click2Call

{
  "author": "CommPeak",
  "homepage_url": "https://www.commpeak.com",
  "background": {
    "scripts": [
      "bg/cmmk.js"
    ]
  },
  "description": "CommPeak's Click2Call for PBX",
  "icons": {
    "16": "img/cmmk16.png",
    "48": "img/cmmk48.png",
    "128": "img/cmmk128.png"
  },
  "manifest_version": 2,
  "name": "CommPeak - PBX Click2Call",
  "options_page": "options/options.html",
  "permissions": [
    "contextMenus",
    "notifications"
  ],
  "version": "0.0.1.5resigned1",
  "web_accessible_resources": [
    "img/*.png"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "@commpeakpbxclick2call"
    }
  }
}