Examine source code of Astronaut Space Walk

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#6a8eab",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Astronaut Space Walk",
  "manifest_version": 2,
  "description": "Image credit: Comfreak \n<a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/b2541aac5394c44574f1a6881e8e9c70efe89fefe70a4245b9564c41b0b79234/https%3A//pixabay.com/en/users/Comfreak-51581/\">https://pixabay.com/en/users/Comfreak-51581/</a>"
}