Examine source code of Reddit Hidden Content Revealer

{
  "manifest_version": 3,
  "name": "Reddit Hidden Activity Revealer",
  "version": "0.8.2",
  "description": "Reveals posts/comments a user hid from their profile by re-fetching them from Reddit search and the Arctic Shift index, shown inline with a blue border. Complements RES.",
  "browser_specific_settings": {
    "gecko": {
      "id": "hidden-revealer@emerson",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "*://*.reddit.com/*",
    "https://arctic-shift.photon-reddit.com/*"
  ],
  "icons": {
    "48": "icon.svg",
    "96": "icon.svg"
  },
  "action": {
    "default_title": "Hidden Activity Revealer",
    "default_popup": "popup.html",
    "default_icon": "icon.svg"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.reddit.com/*"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "styles.css"
      ],
      "run_at": "document_end"
    }
  ]
}