Examine source code of Pulse-

{
  "theme": {
    "images": {
      "theme_frame": "pulse_chain3.png"
    },
    "colors": {
      "frame": "#420303",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Pulse-",
  "manifest_version": 2,
  "description": "This is my 1st persona design. Inspired by the horror genre, mostly zombie-type movies/video games."
}