Examine source code of Day&Night

{
  "version": "2.1",
  "name": "Day & Night",
  "description": "__MSG_extension_description__",
  "homepage_url": "https://github.com/evgnz/Day-and-Night",
  "author": "Evgeny Chumichev",
  "manifest_version": 2,
  "default_locale": "en",
  "browser_specific_settings": {
    "gecko": {
      "id": "{f1379f36-0719-4b9a-bd37-4c71475c5268}",
      "strict_min_version": "87.0"
    }
  },
  "permissions": [
    "theme",
    "notifications",
    "management",
    "storage"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "16": "images/logo_16.svg",
    "32": "images/logo_32.svg",
    "48": "images/logo_48.svg",
    "64": "images/logo_64.svg",
    "128": "images/logo_128.svg",
    "256": "images/logo_256.svg"
  },
  "browser_action": {
    "default_icon": {
      "32": "images/logo_32.svg"
    },
    "theme_icons": [
      {
        "light": "images/icon_light.svg",
        "dark": "images/icon_dark.svg",
        "size": 32
      }
    ],
    "default_title": "Day & Night"
  },
  "commands": {
    "switch_theme": {
      "suggested_key": {
        "default": "Ctrl+Shift+Space"
      },
      "description": "__MSG_hotkeys_description__"
    }
  }
}