Examine source code of Priority Matrix for Firefox

{
  "manifest_version": 2,
  "name": "Priority Matrix for Firefox",
  "short_name": "PM-Firefox",
  "description": "Firefox Extension to turn web links into Priority Matrix items.",
  "version": "1.8.37",
  "author": "Appfluence Inc",
  "options_ui": {
    "page": "options/Options.html",
    "open_in_tab": true
  },
  "icons": {
    "16": "images/PM16.png",
    "48": "images/PM48.png",
    "128": "images/PM128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://sync.appfluence.com/*",
        "*://*.appfluence.com/*",
        "*://*.prioritymatrix.com/*",
        "*://*.priority.app/*"
      ],
      "js": [
        "js/jquery-3.3.1.min.js",
        "contentscript/extensionDetector.js"
      ],
      "run_at": "document_start",
      "all_frames": true
    }
  ],
  "background": {
    "scripts": [
      "js/sentry.min.js",
      "js/errorLogger.js",
      "background/contextMenu.js",
      "js/jquery-3.3.1.min.js",
      "background/feedback.js",
      "background/checkFirstuse.js"
    ]
  },
  "browser_action": {
    "default_icon": "images/PM.png",
    "default_popup": "popup/popup.html",
    "default_title": "Priority Matrix"
  },
  "web_accessible_resources": [
    "js/sentry.min.js",
    "js/errorLogger.js",
    "background/contextMenu.js",
    "background/feedback.js",
    "background/checkFirstuse.js",
    "popup/popup.js",
    "contentscript/extensionDetector.js",
    "images/logo_head.png",
    "images/flying_envelope_2.gif",
    "js/jquery-3.3.1.min.js",
    "js/jquery-ui.js",
    "js/jquery.dropdown.min.js",
    "js/select2.min.js",
    "css/select2.min.css",
    "css/jquery-ui.css",
    "css/bootstrap.min.css",
    "css/base.css",
    "settings.js"
  ],
  "permissions": [
    "contextMenus",
    "activeTab",
    "<all_urls>",
    "https://sync.appfluence.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "firefox@appfluence.com",
      "strict_min_version": "58.0"
    }
  }
}