Examine source code of Better Vertretungsplan

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  "name": "Better Vertretungsplan",
  "description": "",
  "version": "3.0.1",
  "manifest_version": 3,
  "icons": {
    "24": "images/logo_24.png",
    "48": "images/logo_48.png"
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    "gecko_android": {}
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        "*://localhost/*",
        "*://*.localhost/*"
      ],
      "match_about_blank": true,
      "all_frames": true,
      "css": [
        "mobile.css"
      ],
      "js": [
        "mobile.js"
      ],
      "run_at": "document_end"
    },
    {
      "matches": [
        "https://fsg-preetz.org/iserv/auth/*"
      ],
      "exclude_matches": [
        "*://localhost/*",
        "*://*.localhost/*"
      ],
      "match_about_blank": true,
      "all_frames": true,
      "css": [
        "auth.css"
      ],
      "js": [
        "auth.js"
      ],
      "run_at": "document_start"
    },
    {
      "matches": [
        "https://fsg-preetz.org/iserv/*"
      ],
      "exclude_matches": [
        "*://localhost/*",
        "*://*.localhost/*"
      ],
      "match_about_blank": true,
      "all_frames": true,
      "js": [
        "iserv.js"
      ],
      "run_at": "document_end"
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "images/*"
      ],
      "matches": [
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      ]
    }
  ]
}