Examine source code of OlderFlow

{
  "manifest_version": 2,
  "name": "OlderFlow",
  "version": "1.0",
  "developer": {
    "name": "Gabriel Rezende",
    "url": "https://github.com/rezendecomz/olderFlow"
  },
  "description": "A extension made to facilitate the search process on Q&A sites using colors, copy buttons and shortcuts. For now is compatible with Stackoverflow and Stackexchange. Search compatible with Google and DuckDuckGo.",
  "icons": {
    "48": "icons/olderFlow-48.png",
    "96": "icons/olderFlow-96.png"
  },
  "options_ui": {
    "page": "pages/options.html",
    "browser_style": true
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.stackoverflow.com/*",
        "https://*.stackexchange.com/*"
      ],
      "js": [
        "./scripts/olderFlow.js"
      ]
    },
    {
      "matches": [
        "*://*.google.com/*"
      ],
      "js": [
        "./scripts/google.js"
      ]
    },
    {
      "matches": [
        "*://*.duckduckgo.com/*"
      ],
      "js": [
        "./scripts/duckduckgo.js"
      ]
    }
  ]
}