Examine source code of Reviewboard Collapser

{
  "name": "Reviewboard Collapser",
  "version": "1.2resigned1",
  "manifest_version": 2,
  "author": "Blake Winton (https://bwinton.latte.ca/)",
  "description": "A WebExtension to add a collapse button to files in ReviewBoard requests.",
  "permissions": [
    "tabs"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://reviewboard.mozilla.org/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ],
  "applications": {
    "gecko": {
      "id": "reviewboard-collapser@webextensions"
    }
  }
}