Examine source code of Peace time.

{
  "theme": {
    "images": {
      "theme_frame": "a-618-mo-yasuraghitotoki.jpg"
    },
    "colors": {
      "frame": "#e6ebdf",
      "tab_background_text": "#000105"
    }
  },
  "version": "2.0",
  "name": "Peace time.",
  "manifest_version": 2,
  "description": "休憩タイム。"
}