Examine source code of Reader View Plus

{
  "description": "reading mode alternative",
  "manifest_version": 2,
  "name": "reader view",
  "version": "0.2.0",
  "browser_specific_settings": {
    "gecko": {
      "id": "@mimv.readerview",
      "strict_min_version": "115.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "icons": {
    "16": "icon-small.58f01a10.svg",
    "32": "icon.26cbc4e2.svg",
    "48": "icon.26cbc4e2.svg",
    "96": "icon.26cbc4e2.svg"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.7a7c3b70.js"
      ],
      "css": []
    }
  ],
  "background": {
    "scripts": [
      "background.74237cdb.js"
    ]
  },
  "browser_action": {
    "default_icon": "icon-small.58f01a10.svg",
    "default_title": "reader view"
  },
  "web_accessible_resources": [
    "index.html"
  ],
  "permissions": [
    "activeTab",
    "storage",
    "history"
  ]
}