For the exported epub, some chapters are not properly linked in the manifest/spine

[kolyb0416]

Steps to reproduce

1. Export epub with reader theme and custom CSS.
2. Copy the epub file to a computer
3. View it on calibre

Expected behavior

All chapters should be viewable

Actual behavior

Some chapters cannot be accessed

LNReader version

2.0.0

Android version

Android 15

Device

Redmi Note 12

Other details

Calibre 8.7.0 Windows 11

I do not know much of programming or about epubs but when trying to edit the epub file using calibre, it seems that the link to the file in the manifest/spine for some chapters is a bit weird, such as the one in the picture. After removing the part in the red circle, everything was fine.

Acknowledgements

• [x] I have searched the existing issues and this is a new ticket, NOT a duplicate or related to another open or closed issue.
• [x] I have written a short but informative title.
• [x] If this is an issue with a source, I should be opening an issue in the sources repository.
• [x] I have updated the app to version 2.0.0.
• [x] I will fill out all of the requested information in this form.