Examine source code of Stats Navigator

{
  "manifest_version": 2,
  "name": "Stats Navigator",
  "description": "Linking between Baseball-Reference, Baseball Savant, and Fangraphs",
  "version": "1.4.0",
  "browser_action": {
    "default_icon": "newIcon.png",
    "default_popup": "popup.html"
  },
  "permissions": [
    "activeTab"
  ]
}