Examine source code of rebel74

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#858282",
      "tab_background_text": "#a30000"
    }
  },
  "version": "2.0",
  "name": "rebel74",
  "manifest_version": 2,
  "description": "a background i found online and edited down to just say rebel."
}