Problem:

As of 2023-07 our old ISBN fetcher from ebooks.de is non-operational, because ebook.de has closed down their API. (See #9979)

Solution/Workaround:

Explore alternative fetchers. For example:

• https://pypi.org/project/isbnlib/
• https://openlibrary.org/dev/docs/api/books

Alternative fetchers, for which users would require an API key (One would have to pay for the API key or "somehow" aquire one):

• Support Worldcat.org as fetcher #1065