Examine source code of Tab Dedupe

{
  "manifest_version": 2,
  "name": "Tab Dedupe",
  "description": "Remove duplicates of the current tab",
  "version": "1.1resigned1",
  "homepage_url": "https://github.com/mauforonda/tabdedupe",
  "applications": {
    "gecko": {
      "id": "tabdedupe@mauforonda",
      "strict_min_version": "55.0a1"
    }
  },
  "icons": {
    "48": "icon.svg",
    "96": "icon.svg"
  },
  "browser_action": {
    "default_title": "Tab Dedupe",
    "default_popup": "popup.html",
    "default_icon": "icon.svg"
  },
  "permissions": [
    "tabs"
  ]
}