Examine source code of goSuperDark

{
  "manifest_version": 3,
  "name": "goSuperDark",
  "version": "1.0.20",
  "description": "Darkmode for goSupermodel",
  "icons": {
    "48": "icon.png",
    "96": "icon.png",
    "128": "icon.png"
  },
  "action": {
    "default_icon": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{8d45fbbc-62bf-4dc7-b03b-ff014dacb83e}"
    }
  },
  "content_scripts": [
    {
      "js": [
        "insert-darkmode.js"
      ],
      "matches": [
        "https://gosupermodel.com/*"
      ]
    },
    {
      "css": [
        "variables.css",
        "official copy.css",
        "better-gsm.css",
        "inventory.auction.css",
        "friendbadges.css",
        "creative.magazines.css",
        "scoop.css",
        "decor.css"
      ],
      "matches": [
        "https://gosupermodel.com/*"
      ],
      "run_at": "document_start"
    },
    {
      "css": [
        "billing.css"
      ],
      "matches": [
        "https://gosupermodel.com/billing/*"
      ],
      "run_at": "document_start"
    },
    {
      "css": [
        "fame.css"
      ],
      "matches": [
        "https://gosupermodel.com/profiles/fame.jsp*"
      ]
    },
    {
      "css": [
        "inventory.css",
        "inventory.contextnavigator.css",
        "inventory.filternavigator.css"
      ],
      "matches": [
        "https://gosupermodel.com/shopping/*"
      ],
      "run_at": "document_start"
    },
    {
      "css": [
        "pictureshare.css"
      ],
      "matches": [
        "https://gosupermodel.com/profiles/picture_archive.jsp*"
      ],
      "run_at": "document_start"
    },
    {
      "css": [
        "fmb.css"
      ],
      "matches": [
        "https://gosupermodel.com/community",
        "https://gosupermodel.com/community/",
        "https://gosupermodel.com/community/index.jsp",
        "https://gosupermodel.com/profiles/friend_message_board_show_post.jsp*"
      ],
      "run_at": "document_start"
    },
    {
      "css": [
        "games.page.css"
      ],
      "matches": [
        "https://gosupermodel.com/games",
        "https://gosupermodel.com/games/",
        "https://gosupermodel.com/games/index.jsp",
        "https://gosupermodel.com/games/backstage_menu.jsp"
      ],
      "run_at": "document_start"
    },
    {
      "css": [
        "games.sketchit.css"
      ],
      "matches": [
        "https://gosupermodel.com/games/*",
        "https://gosupermodel.com/skinv/*",
        "https://gosupermodel.com/community/club_page.jsp?clubid=2243&pageid=3102*"
      ],
      "run_at": "document_start"
    },
    {
      "css": [
        "creative.css"
      ],
      "matches": [
        "https://gosupermodel.com/creative/",
        "https://gosupermodel.com/creative/index.jsp"
      ],
      "run_at": "document_start"
    },
    {
      "css": [
        "creative.jd.css"
      ],
      "matches": [
        "https://gosupermodel.com/creative/juniordesigner/*"
      ],
      "run_at": "document_start"
    },
    {
      "css": [
        "creative.designer.css"
      ],
      "matches": [
        "https://gosupermodel.com/creative/my_designs.jsp*"
      ],
      "run_at": "document_start"
    }
  ]
}