I already have a fix for this, just reporting it for transparency's sake. This was very possibly a dumb idea, but we decided in papyri.info to deal with multiple ancient diacritics using, e.g. <hi rend="diaeresis"><hi rend="acute">α</hi></hi> instead of what would probably have been saner, <hi rend="diaeresis acute">α</hi>. The Stylesheets do not cope with every possible combination of these. They'll do diaeresis acute, I believe, but not asper circumflex. Certainly, some combinations are "impossible" (though I'm not sure I'd bet money on that), but I think it's better we not make that judgement in the XSLT. So I have a solution that will just combine whatever it's given correctly. Note that "correctly" means "in order of proximity to the text", so from the inside out. That sometimes has an affect on rendering because combining diacritics can stack differently depending on order.
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