Examine source code of AddLinks: books

{
  "manifest_version": 3,
  "name": "AddLinks: Books",
  "description": "Connect your book world. Deep links between Goodreads, StoryGraph, and Libraries.",
  "default_locale": "en",
  "version": "1.7.3",
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "*://*.abebooks.com/*",
    "*://*.adlibris.com/*",
    "*://*.akademibokhandeln.se/*",
    "*://*.alibris.co.uk/*",
    "*://*.alibris.com/*",
    "*://*.amazon.ca/*",
    "*://*.amazon.co.uk/*",
    "*://*.amazon.com.be/*",
    "*://*.amazon.com.br/*",
    "*://*.amazon.com.mx/*",
    "*://*.amazon.com/*",
    "*://*.amazon.de/*",
    "*://*.amazon.es/*",
    "*://*.amazon.fr/*",
    "*://*.amazon.it/*",
    "*://*.amazon.nl/*",
    "*://*.amazon.pl/*",
    "*://*.amazon.se/*",
    "*://*.antikvariat.net/*",
    "*://*.ark.no/*",
    "*://*.audible.co.uk/*",
    "*://*.audible.com/*",
    "*://*.audible.de/*",
    "*://*.barnesandnoble.com/*",
    "*://*.betterworldbooks.com/*",
    "*://*.bibliotek.dk/*",
    "*://*.blackwells.co.uk/*",
    "*://*.bog-ide.dk/*",
    "*://*.bokus.com/*",
    "*://*.bol.com/*",
    "*://*.booksamillion.com/*",
    "*://*.buscalibre.cl/*",
    "*://*.buscalibre.com.ar/*",
    "*://*.buscalibre.com.mx/*",
    "*://*.casadellibro.com/*",
    "*://*.cuspide.com/*",
    "*://*.ebay.ca/*",
    "*://*.ebay.co.uk/*",
    "*://*.ebay.com/*",
    "*://*.ebay.de/*",
    "*://*.ebay.ie/*",
    "*://*.elefant.ro/*",
    "*://*.empik.com/*",
    "*://*.estantevirtual.com.br/*",
    "*://*.everand.com/*",
    "*://*.fnac.com/*",
    "*://*.gandhi.com.mx/*",
    "*://*.genialokal.de/*",
    "*://*.goodreads.com/*",
    "*://*.ibs.it/*",
    "*://*.instagram.com/*",
    "*://*.librarything.com/*",
    "*://*.librex.ro/*",
    "*://*.libristo.bg/*",
    "*://*.libristo.cz/*",
    "*://*.libristo.eu/*",
    "*://*.libristo.gr/*",
    "*://*.libristo.hr/*",
    "*://*.libristo.hu/*",
    "*://*.libristo.pl/*",
    "*://*.libristo.ro/*",
    "*://*.libristo.si/*",
    "*://*.libristo.sk/*",
    "*://*.liternet.ro/*",
    "*://*.mcnallyrobinson.com/*",
    "*://*.minreol.dk/*",
    "*://*.norli.no/*",
    "*://*.pendulo.com/*",
    "*://*.powells.com/*",
    "*://*.saxo.com/*",
    "*://*.suomalainen.com/*",
    "*://*.thalia.de/*",
    "*://*.thestorygraph.com/*",
    "*://*.thriftbooks.com/*",
    "*://*.waterstones.com/*",
    "*://*.williamdam.dk/*",
    "*://*.wob.com/*",
    "*://*.wordery.com/*",
    "*://*.worldcat.org/*",
    "*://*.worldofbooks.com/*",
    "*://ark.no/*",
    "*://bibliotek.dk/*",
    "*://blackwells.co.uk/*",
    "*://books.google.com/*",
    "*://books.google.de/*",
    "*://books.google.dk/*",
    "*://books.google.fi/*",
    "*://books.google.no/*",
    "*://books.google.se/*",
    "*://bookshop.org/*",
    "*://cuspide.com/*",
    "*://lccn.loc.gov/*",
    "*://libro.fm/*",
    "*://litteratursiden.dk/*",
    "*://minreol.dk/*",
    "*://openlibrary.org/*",
    "*://search.catalog.loc.gov/*",
    "*://uk.bookshop.org/*",
    "*://www.google.com/*",
    "*://www.google.de/*",
    "*://www.google.dk/*",
    "*://www.google.fi/*",
    "*://www.google.no/*",
    "*://www.google.se/*",
    "*://www.kobo.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "addlinks@tc.dk",
      "strict_min_version": "142.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.abebooks.com/*",
        "*://*.adlibris.com/fi/kirja/*",
        "*://*.adlibris.com/nb/bok/*",
        "*://*.adlibris.com/no/bok/*",
        "*://*.adlibris.com/se/bok/*",
        "*://*.adlibris.com/sv/bok/*",
        "*://*.akademibokhandeln.se/bok/*",
        "*://*.alibris.co.uk/*/book/*",
        "*://*.alibris.co.uk/book/*",
        "*://*.alibris.com/*/book/*",
        "*://*.alibris.com/book/*",
        "*://*.amazon.ca/*",
        "*://*.amazon.co.uk/*",
        "*://*.amazon.co.uk/*/hz/wishlist/ls/*",
        "*://*.amazon.co.uk/hz/wishlist/ls/*",
        "*://*.amazon.com.be/*",
        "*://*.amazon.com.br/*",
        "*://*.amazon.com.mx/*",
        "*://*.amazon.com/*",
        "*://*.amazon.com/*/hz/wishlist/ls/*",
        "*://*.amazon.com/hz/wishlist/ls/*",
        "*://*.amazon.de/*",
        "*://*.amazon.de/*/hz/wishlist/ls/*",
        "*://*.amazon.de/hz/wishlist/ls/*",
        "*://*.amazon.es/*",
        "*://*.amazon.fr/*",
        "*://*.amazon.it/*",
        "*://*.amazon.nl/*",
        "*://*.amazon.pl/*",
        "*://*.amazon.se/*",
        "*://*.antikvariat.net/*",
        "*://*.ark.no/boker/*",
        "*://*.ark.no/produkt/*",
        "*://*.audible.co.uk/pd/*",
        "*://*.audible.com/pd/*",
        "*://*.audible.de/pd/*",
        "*://*.barnesandnoble.com/w/*",
        "*://*.betterworldbooks.com/product/detail/*",
        "*://*.bibliotek.dk/*",
        "*://*.blackwells.co.uk/*",
        "*://*.bog-ide.dk/*",
        "*://*.bokus.com/bok/*",
        "*://*.bol.com/*/p/*",
        "*://*.booksamillion.com/*",
        "*://*.buscalibre.cl/*",
        "*://*.buscalibre.com.ar/*",
        "*://*.buscalibre.com.mx/*",
        "*://*.casadellibro.com/ebook-*",
        "*://*.casadellibro.com/libro-*",
        "*://*.casadellibro.com/libros/*",
        "*://*.cuspide.com/*",
        "*://*.ebay.ca/itm/*",
        "*://*.ebay.co.uk/itm/*",
        "*://*.ebay.com/itm/*",
        "*://*.ebay.de/itm/*",
        "*://*.ebay.ie/itm/*",
        "*://*.elefant.ro/*",
        "*://*.empik.com/*-p*",
        "*://*.estantevirtual.com.br/*",
        "*://*.everand.com/*",
        "*://*.fnac.com/*",
        "*://*.gandhi.com.mx/*",
        "*://*.genialokal.de/*",
        "*://*.goodreads.com/book/show/*",
        "*://*.ibs.it/*",
        "*://*.instagram.com/*",
        "*://*.librarything.com/work/*",
        "*://*.librex.ro/*",
        "*://*.libristo.bg/*",
        "*://*.libristo.cz/*",
        "*://*.libristo.eu/*",
        "*://*.libristo.gr/*",
        "*://*.libristo.hr/*",
        "*://*.libristo.hu/*",
        "*://*.libristo.pl/*",
        "*://*.libristo.ro/*",
        "*://*.libristo.si/*",
        "*://*.libristo.sk/*",
        "*://*.liternet.ro/*",
        "*://*.mcnallyrobinson.com/*",
        "*://*.minreol.dk/*",
        "*://*.norli.no/*",
        "*://*.pendulo.com/libro/*",
        "*://*.powells.com/book/*",
        "*://*.saxo.com/*",
        "*://*.suomalainen.com/products/*",
        "*://*.thalia.de/*",
        "*://*.thestorygraph.com/*",
        "*://*.thriftbooks.com/w/*",
        "*://*.waterstones.com/book/*",
        "*://*.williamdam.dk/*",
        "*://*.wob.com/*/books/*",
        "*://*.wordery.com/*",
        "*://*.worldcat.org/title/*",
        "*://*.worldofbooks.com/*/products/*",
        "*://ark.no/boker/*",
        "*://bibliotek.dk/*",
        "*://blackwells.co.uk/*",
        "*://books.google.com/books*",
        "*://books.google.de/books*",
        "*://books.google.dk/books*",
        "*://books.google.fi/books*",
        "*://books.google.no/books*",
        "*://books.google.se/books*",
        "*://bookshop.org/books/*",
        "*://bookshop.org/p/books/*",
        "*://cuspide.com/*",
        "*://lccn.loc.gov/*",
        "*://libro.fm/audiobooks/*",
        "*://litteratursiden.dk/*",
        "*://minreol.dk/*",
        "*://openlibrary.org/books/*",
        "*://openlibrary.org/works/*",
        "*://search.catalog.loc.gov/*",
        "*://uk.bookshop.org/*",
        "*://www.google.com/books*",
        "*://www.google.de/books*",
        "*://www.google.dk/books*",
        "*://www.google.fi/books*",
        "*://www.google.no/books*",
        "*://www.google.se/books*",
        "*://www.kobo.com/*"
      ],
      "js": [
        "config.js",
        "icons.js",
        "content.js"
      ],
      "run_at": "document_idle"
    }
  ]
}