Examine source code of Red Highlights

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Red Highlights",
  "theme": {
    "images": {},
    "properties": {},
    "colors": {
      "toolbar": "rgb(25, 13, 13)",
      "toolbar_text": "rgb(255, 0, 0)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(255, 0, 0)",
      "toolbar_field": "rgb(0, 0, 0)",
      "toolbar_field_text": "rgb(255, 0, 0)",
      "tab_line": "rgb(255, 0, 0)",
      "popup": "rgb(0, 0, 0)",
      "popup_text": "rgb(255, 0, 0)",
      "icons_attention": "rgb(255, 0, 0)",
      "ntp_background": "rgb(25, 13, 13)",
      "popup_border": "rgb(255, 0, 0)",
      "popup_highlight_text": "rgb(255, 0, 0)",
      "popup_highlight": "rgb(78, 0, 0)",
      "tab_text": "rgb(255, 255, 255)",
      "toolbar_bottom_separator": "rgb(255, 0, 0)",
      "toolbar_field_border_focus": "rgb(255, 0, 0)",
      "toolbar_field_border": "rgb(255, 0, 0)",
      "toolbar_field_highlight": "rgb(78, 0, 0)",
      "toolbar_field_text_focus": "rgb(255, 0, 0)",
      "tab_loading": "rgb(255, 0, 0)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{5635062c-96e1-46e8-b0eb-a207c819d00d}"
    }
  }
}