Examine source code of Caffeine - Keep Awake

{
  "manifest_version": 3,
  "version": "0.3.1",
  "name": "Caffeine - Keep Awake",
  "description": "Prevent screen dimming or activating a screen saver by overriding power-saving settings to keep the system or display awake",
  "permissions": [
    "storage",
    "power",
    "idle",
    "contextMenus",
    "alarms",
    "offscreen"
  ],
  "optional_permissions": [
    "downloads"
  ],
  "icons": {
    "16": "data/icons/16.png",
    "32": "data/icons/32.png",
    "48": "data/icons/48.png",
    "64": "data/icons/64.png",
    "128": "data/icons/128.png",
    "256": "data/icons/256.png",
    "512": "data/icons/512.png"
  },
  "background": {
    "service_worker": "worker.js",
    "scripts": [
      "firefox.js",
      "context.js",
      "downloads.js",
      "worker.js"
    ]
  },
  "action": {
    "default_icon": {
      "16": "data/icons/disabled/16.png",
      "32": "data/icons/disabled/32.png",
      "48": "data/icons/disabled/48.png"
    }
  },
  "homepage_url": "https://webextension.org/listing/caffeine.html",
  "commands": {
    "_execute_action": {}
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{1ed1eedc-d15d-451e-be52-7303adf1a0d2}",
      "strict_min_version": "148.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}