[davidfor]

Originally Posted by Regard_39

I have to digest this avalanche of information. I realized that my idea was dead end. Also, it seemed to me that by looking at the contents of the folder of each ebook, the metadata.opf file was shared by the epub and the kepub.

That metadata.opf file is created by calibre. There is one for every book you have in the calibre library not matter what format. Or if there is no format. But, it is really just a backup of the metadata for the book that is in the database calibre uses. If that gets corrupted, calibre can recover the library using these files.

I wonder though why the kepub file generated by kobotouchextended does not go into a temporary file. Shouldn't on the fly behave like this? So you have to delete the kepub manually once it is transferred to the e-reader. Maybe there is a setting to delete it automatically.
And do you leave your kepubs or do you delete them?

That was a deliberate design choice. The point of the extended driver is to generate a kepub without going through the full conversion. At the time the extended driver was created, none of the other plugins needed to manage kepubs existed. As the only use for a kepub was on a Kobo device, adding it back to the library was not thought useful. And for most people it isn't useful.

The plugin does have an option to store the generated file elsewhere, but, I think of that mainly to help with debugging.

I did not report the error and unfortunately I could not find on which Kobo e-reader and which ebook I had this failure. Mea culpa.

If you work it out, or see the problem again, report it then. Of course, the problem might have been fixed in some other way.

In fact I discovered by chance kepubify far from home and it helped me a lot. I secretly hoped to find a way to combine the speed performance of kepubify and still enjoy Calibre. Wrong way it seems.

Someone was looking at a plugin that used kepubify, but, I don't remember what happened. And unless you are sending a lot of books at a time, the performance isn't that meaningful. And calibre or the driver does a lot more than just generate the kepub when sending the books. It also updates the metadata, the cover, does the copy, updates the metadata.calibre file for book matching, collection management and some other things.