Examine source code of grassy mushrooms

{
  "manifest_version": 2,
  "version": "1.1",
  "name": "grassy mushrooms",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(84, 143, 79, 0.8)",
      "toolbar_text": "rgba(4, 26, 6, 0.93)",
      "frame": "rgb(84, 143, 79)",
      "tab_background_text": "rgb(5, 44, 36)",
      "toolbar_field": "rgba(255, 241, 0, 0.76)",
      "toolbar_field_text": "rgb(7, 63, 52)",
      "tab_line": "rgb(7, 63, 52)",
      "popup": "rgba(84, 143, 79, 0.8)",
      "popup_text": "rgb(0, 0, 0)",
      "button_background_active": "rgba(255, 0, 83, 0.79)",
      "frame_inactive": "rgba(255, 241, 0, 0.79)",
      "icons_attention": "rgb(131, 17, 56)",
      "icons": "rgb(7, 63, 52)",
      "ntp_background": "rgba(4, 26, 6, 0.93)",
      "ntp_text": "rgb(7, 63, 52)",
      "popup_border": "rgba(255, 241, 0, 0.79)",
      "popup_highlight_text": "rgba(255, 0, 83, 0.79)",
      "popup_highlight": "rgba(255, 0, 83, 0.79)",
      "sidebar_border": "rgb(7, 63, 52)",
      "sidebar_highlight_text": "rgba(255, 0, 83, 0.79)",
      "sidebar_highlight": "rgba(255, 241, 0, 0.76)",
      "sidebar_text": "rgb(5, 44, 36)",
      "tab_loading": "rgb(7, 63, 52)"
    }
  }
}