Examine source code of Titles Extension

{
  "manifest_version": 2,
  "name": "Titles Extension",
  "version": "2.6.1",
  "description": "Extension to get page titles and urls and format them as HTML, Markdown or for a Wiki to speed up and improve copying links",
  "homepage_url": "https://www.geoffdoesstuff.com/titles-extension",
  "icons": {
    "32": "icons/gds_logo_32.png",
    "48": "icons/gds_logo_48.png"
  },
  "permissions": [
    "activeTab",
    "clipboardWrite",
    "tabs"
  ],
  "browser_action": {
    "default_icon": "icons/gds_logo_32.png",
    "default_title": "Titles Extension",
    "default_popup": "popup/titles-extension-popup.html"
  }
}