Greasy Fork is available in English.
generate a button for borrowed Internet Archive books.
Show a button for downloading PDF for borrowed books @ Internet Archive.
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Please note as of Nov. 11th, 2024, the script no longer works because Internet Archive is having issues offering borrowed books to download.
Meanwhile, the new Internet Archive has a new UI which has a dot button (...) on the left of the book view, which gives you an option for "Downloadable files".
It means it effectively made the script meaningless because you can now use the official way to download the ACSM PDF.
But still, as of now, the Internet Archive is having issues with the PDF download as noted above even with the official download options.