Bug? 320 footnotes created on import to Calibre

[catkin]

I think this is a bug but want to invite comments before reporting it.

The book was "Arsène Lupin, super-sleuth" by Maurice Leblanc, https://www.gutenberg.org/ebooks/74269.

When viewed online at https://www.gutenberg.org/cache/epub...69-images.html the first chapter's first page had no visible footnotes (I don't know for sure that footnotes are displayed when viewing online).

After downloading the "EPUB3 (E-readers incl. Send-to-Kindle)" version, importing to Calibre 7.20.0 and opening the book, the first chapter's first page had footnote number 12 after "make a careful examination of these two persons". No footnote footer is displayed and I was not able to open the footnote (I don't read books in Calibre so am not familiar with footnote usage). The last chapter's last page had footnote 320 after "The child, corrupted too early, could not rise from the depths".

After using Calibre 7.20.0 to send the book to a Kobo Aura H2O and opening the book, the same footnotes were visible. When opened they showed the content of the page they were on.

One unusual feature of the book which may have triggered the bug is a colophon listing 50 corrections with links to the corrected text which appears with a faint underline in the text

[kovidgoyal]

Importing a book into calibre does not change it in any way. It will be byte for byte identical after importing, unless you have third party filetype plugins installed.

[PeterT]

I wonder when you sent the book to Kobo were you sending it as a native ePub or using any of the kEpub plugins?

[readx]

These are page numbers in the original epub and they show as intended.
It's not a bug and has nothing to do with calibre.

<span class="pageNum" id="pb37">[<a href="6886765827878775779_74269-h-2.htm.xhtml#pb37" class="pginternal">37</a>]</span>

[PeterT]

From looking at the book, the 12 is NOT a footnote; rather it's a page number!

I've not checked other "footnotes" but I think it's safe to say they all follow the same pattern.

Ralph de Limézy was no less discreet, and availing
himself of the screen afforded by the throng, he quickened his steps in order to make
a careful examination of these two persons.
<span class="pageNum" id="pb12">[<a href="6886765827878775779_74269-h-1.htm.xhtml#pb12" class="pginternal">12</a>]</span></p>

[catkin]

Originally Posted by PeterT

I wonder when you sent the book to Kobo were you sending it as a native ePub or using any of the kEpub plugins?

As a kEpub. Calibre's Device tab lists it with filename ending in .kepub.epub. I'm not sure which plugin does the conversion so here's all of them

• Kobo Touch Extended (3.7.0) by Joel Coguen
• KePub Metadata Reader (3.4.3) by David Forrester
• KePub Metadata Writer (3.4.3) by David Forrester
• Kobo Utilities (2.17.2) by David Forrester