Examine source code of Dynamic Base16

{
  "manifest_version": 2,
  "name": "Dynamic Base16",
  "version": "1.0.1",
  "description": "Dynamic Firefox base16 theme switcher extension, using native messaging.",
  "browser_specific_settings": {
    "gecko": {
      "id": "dynamic_base16@gnrl_leclerc.org",
      "strict_min_version": "78.0"
    }
  },
  "icons": {
    "48": "assets/tinted_48.png",
    "96": "assets/tinted_96.png"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "nativeMessaging",
    "theme"
  ]
}