Examine source code of Seasons Series - Spring

{
  "theme": {
    "images": {
      "theme_frame": "Seasons-SpringHeader.jpg"
    },
    "colors": {
      "frame": "rgba(229,230,232,1)",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "Seasons Series - Spring",
  "manifest_version": 2,
  "description": "Illustration \"Seasons Series - Spring\"\n\nCreate your Firefox with the current season by using my Seasons Series.\nOriginal artwork available here: <a href=\"https://outgoing.prod.mozaws.net/v1/a1ecaf2419d98733ca17b546c2fa0c55242447e502205e338306963fbfe49679/http%3A//www.posterlounge.com/mandy-reinmuth-a1/poster-spring-seasons-serie-pr2485-t3.html\" rel=\"nofollow\">http://www.posterlounge.com/mandy-reinmuth-a1/poster-spring-seasons-serie-pr2485-t3.html</a>"
}