Examine source code of Heartstopper Black Theme

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Heartstopper Black Theme",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(12, 12, 14)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(4, 4, 4)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(33, 33, 38)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(249, 78, 143)",
      "popup": "rgb(12, 12, 14)",
      "popup_text": "rgb(255, 255, 255)",
      "icons": "rgb(241, 200, 148)",
      "ntp_background": "rgb(23, 23, 30)",
      "tab_selected": "rgb(9, 9, 11)",
      "toolbar_bottom_separator": "rgb(145, 253, 108)",
      "tab_loading": "rgb(249, 78, 143)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{980bf2f2-0dd3-4fd3-b067-cb53dda137f8}"
    }
  }
}