Examine source code of Material (Light)

{
  "manifest_version": 2,
  "name": "Material (Light)",
  "version": "2.0",
  "description": "Provides a light Material color palette to accompany the MaterialFox userChrome.css theme.",
  "homepage_url": "https://github.com/muckSponge/MaterialFox",
  "browser_specific_settings": {
    "gecko": {
      "id": "material-light@mucksponge"
    }
  },
  "theme": {
    "colors": {
      "icons": "#606368",
      "icons_attention": "#5086ec",
      "button_background_hover": "rgba(0, 0, 0, .07)",
      "button_background_active": "rgba(0, 0, 0, .11)",
      "toolbar": "#fff",
      "toolbar_bottom_separator": "#b3b1b3",
      "popup_highlight": "#0056d9",
      "popup_highlight_text": "#fff",
      "frame": "#dee1e6",
      "tab_background_text": "#606368",
      "bookmark_text": "#606368"
    }
  }
}