Examine source code of Summer Fireflies

{
  "name": "Summer Fireflies",
  "manifest_version": 2,
  "version": "5.0",
  "theme": {
    "images": {
      "theme_frame": "SummerFirefliesHCustom.jpg"
    },
    "colors": {
      "frame": "rgba(31, 1, 1, 1)",
      "tab_background_text": "rgba(255, 255, 3, 1)",
      "toolbar": "rgba(0, 0, 0, 0)",
      "bookmark_text": "rgba(255, 255, 0, 1)",
      "toolbar_field": "rgba(31, 1, 1, 0.09)",
      "toolbar_field_text": "rgba(255, 255, 0, 1)",
      "tab_line": "rgba(255, 255, 0, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{07c34454-bebd-44c6-bdfb-79b62f73af18}"
    }
  }
}