Yep, your best bet on that front will probably ultimately be whatever support for that is in MµPDF, which is probably not going to be much, if any

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On the other hand, we have somewhat decent support for *horizontal* ruby tags, as well as proper support for complex horizontal scripts (e.g., Arabic, Indic)

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EDIT: Ah, dug up the actual
issue. MµPDF said nope, not gonna happen either

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