[mdaniel]

> It like every other open ePub reader I've tried also has limited to no support for ePub 3

Is there an open issue for that feature gap in KOReader? I'm always curious whether it's just "we haven't gotten there yet" versus "we don't want to do that"

[goosedragons]

Yeah there is for vertical writing (https://github.com/koreader/koreader/issues/4353) at least. It seems like it's a limitation of their engines so I don't blame them.