Examine source code of Search Transparency 3

{
  "theme": {
    "images": {
      "theme_frame": "Search-Transparency-Header-33000x200.jpg"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "Search Transparency 3",
  "manifest_version": 2,
  "description": "<a href=\"https://outgoing.prod.mozaws.net/v1/fc4b3e257806f6033a040a11ea939836b8dad2c27fbc862fc1126e1274375a5f/http%3A//www.searchtransparencysem.com\" rel=\"nofollow\">http://www.searchtransparencysem.com</a>"
}