Examine source code of periphery

{
  "theme": {
    "images": {
      "theme_frame": "hdr-header.png"
    },
    "colors": {
      "frame": "rgba(229,230,232,1)",
      "tab_background_text": "#030303"
    }
  },
  "version": "2.0",
  "name": "periphery",
  "manifest_version": 2,
  "description": "a periphery logo in white font with a black background"
}