Inner wrapper with `overflow:hidden` prevents fragmentation, page stays vertically scrollable

[v3nko]

Describe the bug

In the reflowable navigator, a resource whose content is wrapped in an inner element styled overflow: hidden does not fragment across pages.

This is related to, but not fixed by, #292 / PR #294. That fix forces overflow: visible !important only on :root and body. It does not touch inner containers, so any content wrapper carrying overflow: hidden still breaks pagination.

Video demo:

Screen_recording_20260708_173117.mp4

Epub: Fundamental-Accessibility-Tests-Non-Visual-Reading-v1.0.0.zip

How to reproduce?

1. Open the attached EPUB
2. Use the reflowable navigator (scroll off) with default settings.
3. Navigate to "Move to the next block item" and swipe 2 pages forward. Its content is wrapped in <section class="sample-text">, styled with overflow: hidden plus ordinary margins/padding.

Readium version

3.3.0

Android API version

36

Additional context

No response

[mickael-menu]

@JayPanoz This should be with Readium CSS v1. Feel free to close if it's already addressed in v2. Thanks!

[JayPanoz]

Hmmmmm I'd like to have @danielweck input here, because I can see this is a file he probably has used and may have encountered ir resolved this issue already.

In the meantime I will test independently of an implementation to see what the result is.