Examine source code of Ram x Rem

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#3d383f",
      "tab_background_text": "#3d383f"
    }
  },
  "version": "2.0",
  "name": "Ram x Rem",
  "manifest_version": 2,
  "description": "Firefox Theme of Ram and Rem from Re: Zero kara Hajimeru Isekai Seikatsu.\n\nAuthor: kazasou\nVisit us on Randomness Thing at <a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/7eb8fd0c67a15ad58872ad7b2460a8d05842ab89c5f24c812e2b8d6e05eb3470/http%3A//randomnessthing.com\">http://randomnessthing.com</a> for more themes!"
}