Examine source code of GitHub Jira Integration

{
  "manifest_version": 2,
  "name": "GitHub Jira Integration",
  "version": "0.1.0",
  "description": "Shows contents of linked tasks from Jira in Github",
  "author": "Adão Raul <adao.raul@gmail.com>",
  "browser_specific_settings": {
    "gecko": {
      "id": "github-jira-integration@adaoraul.dev",
      "strict_min_version": "58.0"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png",
    "256": "icons/icon256.png",
    "512": "icons/icon512.png"
  },
  "browser_action": {
    "default_popup": "action/default_popup.html",
    "default_icon": {
      "16": "action/icon16.png",
      "48": "action/icon48.png",
      "128": "action/icon128.png"
    }
  },
  "options_ui": {
    "page": "options_ui/page.html",
    "open_in_tab": false
  },
  "background": {
    "scripts": [
      "background/service_worker.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "*://github.com/*"
      ],
      "js": [
        "content_scripts/content-0.js"
      ],
      "css": [
        "content_scripts/content-0.css"
      ],
      "run_at": "document_end"
    }
  ],
  "permissions": [
    "storage",
    "cookies",
    "https://*.atlassian.net/*",
    "https://*.jira.com/*",
    "http://*.atlassian.net/*",
    "http://*.jira.com/*"
  ],
  "web_accessible_resources": [
    "icons/jira.png"
  ]
}