Pagination for vertical writing mode ePubs were broken

[JasonHK]

Steps to reproduce

1. Add this sample ePub into the library: 性心情.epub.zip
2. Open it in Komga

Expected behavior

Suppose the viewer should behave like Calibre did there:

Calibre.mp4

Actual behavior

But in reality, the viewer only display the first visible part of each chapter, navigating to next page will switch to next chapter instead:

Komga.mp4

Logs

No response

Komga version

1.18.0

Operating system

Windows 11, Android

Installation method

Docker

Other details

This problem should affect most of the novels written in Japanese and Chinese, which usually written vertically and right-to-left.

Acknowledgements

• I have searched the existing issues (open AND closed) and this is a new ticket, NOT a duplicate or related to another open issue.
• I have written a short but informative title.
• I have checked the FAQ.
• I have updated the app to the latest version.
• I will fill out all of the requested information in this form.

[gotson]

The epub library cannot handle vertical text it seems: d-i-t-a/R2D2BC#1013

[gotson]

Moving this to Ideas, as this never worked in the first place. There's hard limitations on this readium/readium-css#141 which is now parked.