Kobo Libra Colour gets TOC messed up

[LenaWolf]

Hello,

I have a problem when sending ePub files through Calibre to the latest Kobo Libra Colour that I just bought. I am running the latest Calibre 8.15 on Windows 11.

If I just copy that ePub file to Kobo with the File Manager and let Kobo import it and convert it to KePub, everything looks perfect. But if I use the "Send to Device" button in Calibre, the book gets its table of contents messed up: some chapters in the book are being skipped and do not match the same chapters in the table of contents, so when you click on, say, chapter 15 in the TOC, you actually arrive to chapter 5 in the book. The header showing chapters reflects this error (says it's chapter 5 while it is in fact chapter 15).

Now in more detail. I have an ePub file converted from ODT with Calibre. It shows perfectly with the Calibre ePub viewer, it renders perfectly on the Kindle viewer program and on my older Sony eReader, and also if I just copy it to Kobo Libra through the File Manager, it looks perfect there as well. The problem occurs ONLY if I use the "Send to Device" button which makes Calibre convert ePub to KEPub for Kobo.

This book has many images (98 images and 155K words). The TOC begins getting messed up after the images, so it makes me think Calibre misses chapter markers when converting to KEPub. I tried changing the format, such as making sure that each image is displayed on its own page (and in its own XML file), but it makes no difference - every so often a chapter marker is missed. It is not consistent and I could not disover a rule as to when it gets missed, so I could not come up with a universal work-around. Inserting manual page breaks before and after the image does help in some cases, but not always.

My solution for now is not to use "Send to Device" for this eReader but instead copy the file directly, but I thought I'd post about it because this seems to be a bug in Calibre.

I can provide the book for testing purposes.

I hope this helps make Calibre better!
Thank you for your work.

[DNSB]

It would make troubleshooting a lot easier if you could attach the ePub to a message here. One quick suggestion would be to open the ODT file in LibreOffice and then export it as a docx. Import the docx to calibre and convert to ePub to see if that fixes the issue with the ToC.

Just as an aside, a Kobo ereader does not convert to kepub on import.

[LenaWolf]

Originally Posted by DNSB

It would make troubleshooting a lot easier if you could attach the ePub to a message here. One quick suggestion would be to open the ODT file in LibreOffice and then export it as a docx. Import the docx to calibre and convert to ePub to see if that fixes the issue with the ToC.

Just as an aside, a Kobo ereader does not convert to kepub on import.

I am sorry, I cannot attach the book to a message in a public forum because I hope to publish it one day.

As for your suggestion, I do not understand why that would help since the very same epub file looks perfect when it is not converted to Kepub. And again excuse me but something certainly does convert epub to kepub because the Kobo reader shows that file differently. When I use "Send to Device" button, it is stored in Kobo's secret folders and is listed in the book library as a KEPUB. Whereas if I just copy the epub file to the reader with the File Manager, it is converted by the Kobo reader on import and listed as EPUB. It looks differently (not just this file but all others imported via these two routes look differently). So basically EPUB files interpreted by the Kobo reader look correctly but KEPUB files created when pressing "Send to Device" button have this problem.

[Sirtel]

Originally Posted by LenaWolf

I am sorry, I cannot attach the book to a message in a public forum because I hope to publish it one day.

As for your suggestion, I do not understand why that would help since the very same epub file looks perfect when it is not converted to Kepub. And again excuse me but something certainly does convert epub to kepub because the Kobo reader shows that file differently. When I use "Send to Device" button, it is stored in Kobo's secret folders and is listed in the book library as a KEPUB. Whereas if I just copy the epub file to the reader with the File Manager, it is converted by the Kobo reader on import and listed as EPUB. It looks differently (not just this file but all others imported via these two routes look differently). So basically EPUB files interpreted by the Kobo reader look correctly but KEPUB files created when pressing "Send to Device" button have this problem.

You obviously have the Kobo driver in Calibre configured to send kepubs.

[LenaWolf]

Originally Posted by Sirtel

You obviously have the Kobo driver in Calibre configured to send kepubs.

I thought something like this was happening but I could not find where that was set! Do you know how I can disable it?

But anyhow, it seems to be broken for my particular book.

[LenaWolf]

Originally Posted by DNSB

It would make troubleshooting a lot easier if you could attach the ePub to a message here. One quick suggestion would be to open the ODT file in LibreOffice and then export it as a docx. Import the docx to calibre and convert to ePub to see if that fixes the issue with the ToC.

I have just tried exporting as DOCX and then converting it with Calibre... Oh gosh, what a mess. I lost ALL TEXT!!! I don't think this will work for me. I may be allergic to Word. Or the other way around.

[Sirtel]

Originally Posted by LenaWolf

I thought something like this was happening but I could not find where that was set! Do you know how I can disable it?

But anyhow, it seems to be broken for my particular book.

Do you have the Kobo Utilities plugin installed? It's easiest to access the driver via that. Right-click on the plugin icon -> Configure driver -> Collections, covers and uploads -> uncheck Use Kobo viewer for EPUB books

[LenaWolf]

Originally Posted by Sirtel

Do you have the Kobo Utilities plugin installed? It's easiest to access the driver via that. Right-click on the plugin icon -> Configure driver -> Collections, covers and uploads -> uncheck Use Kobo viewer for EPUB books

Thank you! No, I don't have Kobo Utilities plugin, I didn't install any plugins really, it's just what Calibre comes with. But I found a pre-installed Kobo Touch plugin and in there I could disable KEPUB.

The result was interesting: the TOC is fixed but the format is still different from when you just copy files with the File Manager. Kobo still shows it as KEPUB, but I think this time it was Kobo itself that did the conversion because it said "importing files" when I disconnected it from the computer.

Anyway, thank you very much - the problem is solved for me!

This means that there is a bug with the driver of Kobo Touch, alas. If the developer wants to debug it, I can send my book for testing via personal message, just let me know.

Many thanks to everyone involved!

[Sirtel]

Originally Posted by LenaWolf

Thank you! No, I don't have Kobo Utilities plugin, I didn't install any plugins really, it's just what Calibre comes with. But I found a pre-installed Kobo Touch plugin and in there I could disable KEPUB.

The result was interesting: the TOC is fixed but the format is still different from when you just copy files with the File Manager. Kobo still shows it as KEPUB, but I think this time it was Kobo itself that did the conversion because it said "importing files" when I disconnected it from the computer.

Anyway, thank you very much - the problem is solved for me!

This means that there is a bug with the driver of Kobo Touch, alas. If the developer wants to debug it, I can send my book for testing via personal message, just let me know.

Many thanks to everyone involved!

No, Kobo itself doesn't do any converting. If you still get KEPUB, have you perhaps enabled the kepub format for the device and set it as the first preferred format? In the same Kobo Touch settings, check your file formats and disable kepub. Did you uncheck "Use Kobo viewer..."?

[LenaWolf]

Originally Posted by Sirtel

No, Kobo itself doesn't do any converting. If you still get KEPUB, have you perhaps enabled the kepub format for the device and set it as the first preferred format? In the same Kobo Touch settings, check your file formats and disable kepub. Did you uncheck "Use Kobo viewer..."?

Hmm... On the Kobo Touch "Customize Plugin" settings on the first tab "File Formats" I have unchecked kepub (definitely unchecked), so the only formats checked are: epub, pdf, txt, cbz and cbr.

I found "Use Kobo viewer..."! Right on the bottom... And yes, it was checked by default. Unchecked it now. Yes! Now I am getting EPUB, exactly the same as if I were to copy the file with the File Manager.

So it appears that the conversion that sits under "Use Kobo viewer" works correctly, but it's the one under the KEPUB file format that messes up the TOC.

[Sirtel]

Originally Posted by LenaWolf

So it appears that the conversion that sits under "Use Kobo viewer" works correctly, but it's the one under the KEPUB file format that messes up the TOC.

That's interesting. I didn't even know they were different.

[PeterT]

Might I suggest that you make use of the ScrambleEbook calibre plugin to create a scrambled version of this ePub and post it. That will leave the structure of the eBook as is but ensure that the text is replaced by garbage.

[LenaWolf]

Originally Posted by Sirtel

That's interesting. I didn't even know they were different.

Hmm... I don't know if they are different. I have checked and unchecked it a few times now, restarted Calibre and all that, and the KEPUB is now working correctly for the TOC... but the thing is, that neither the ODT nor the converted EPUB changed in between. Plain EPUB always works, KEPUB... depends on whether Jupiter is in my House or not, it seems. May be I should also reboot the PC for good measure. Also sometimes I am getting giant letters and other time miniscule letters, and if I'm lucky, I might get normal sized letters... on the same book! Something fishy is going on here.

But I can live with this! Thank you for pointing me to the settings!

[LenaWolf]

Originally Posted by PeterT

Might I suggest that you make use of the ScrambleEbook calibre plugin to create a scrambled version of this ePub and post it. That will leave the structure of the eBook as is but ensure that the text is replaced by garbage.

I shall look into this, thank you!