Examine source code of Muted Blues

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Muted Blues",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(12, 24, 33)",
      "toolbar_text": "rgb(27, 173, 175)",
      "frame": "rgb(12, 24, 33)",
      "tab_background_text": "rgb(24, 156, 180)",
      "toolbar_field": "rgb(27, 42, 65)",
      "toolbar_field_text": "rgb(88, 173, 172)",
      "tab_line": "rgb(89, 116, 123)",
      "popup": "rgb(27, 42, 65)",
      "popup_text": "rgb(88, 173, 172)",
      "tab_loading": "rgb(89, 116, 123)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{596f00c7-7d48-4b57-a783-0a15537558ec}"
    }
  }
}