Examine source code of NMVS scanner

{
  "manifest_version": 3,
  "name": "NMVS scanner",
  "author": "Māris Vilks <maris.vilks@expect.digital>",
  "version": "1.0.4",
  "description": "Allows DataMatrix code (GTIN) scanning directly into NMVS verification/decommissioning form.",
  "homepage_url": "https://github.com/mvilks/nmvs-scanner",
  "icons": {
    "64": "icons/datamatrix-expectdigital.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://portal-prod-lv.nmvs.eu/NMVS_PORTAL/sn/Serialnumber.xhtml*"
      ],
      "js": [
        "main.js"
      ],
      "css": [
        "css/style.css"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "nmvs-scanner@expect.digital"
    }
  }
}