Examine source code of Hang in there Kitty!

{
  "name": "Hang in there Kitty!",
  "manifest_version": 2,
  "version": "3.0",
  "theme": {
    "images": {
      "theme_frame": "catcratch(without--tear).png"
    },
    "colors": {
      "frame": "rgba(229, 230, 232, 1)",
      "tab_background_text": "rgba(255, 255, 255, 1)",
      "toolbar": "rgba(0, 0, 0, 0)",
      "bookmark_text": "rgba(255, 255, 255, 1)",
      "toolbar_field": "rgba(0, 0, 0, 0)",
      "toolbar_field_text": "rgba(255, 255, 255, 1)",
      "tab_line": "rgba(255, 255, 255, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{9c1fa9e3-aed2-4ff5-8375-8e12cffa9dc3}"
    }
  }
}