Hi, I'm using Prince 15.1 to convert a html with presentation mathml to pdf on alpine linux, when using the verbose option, this is what I see:

prince: loading HTML5 input: test.html
prince: loading document: test.html
prince: Applying style sheets...
prince: Preparing document...
prince: loading document: /usr/local/lib/prince/math/operators.xml
prince: loading document: /usr/local/lib/prince/dtd/mathml2/mathml2.dtd
prince: loading document: /usr/local/lib/prince/dtd/mathml2/mathml2-qname-1.mod
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isoamsa.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isoamsb.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isoamsc.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isoamsn.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isoamso.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isoamsr.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isogrk3.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isomfrk.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isomopf.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isomscr.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso9573-13/isotech.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso8879/isobox.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso8879/isocyr1.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso8879/isocyr2.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso8879/isodia.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso8879/isolat1.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso8879/isolat2.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso8879/isonum.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/iso8879/isopub.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/mathml/mmlextra.ent
prince: loading document: /usr/local/lib/prince/dtd/mathml2/mathml/mmlalias.ent
prince: loading document: /usr/local/lib/prince/math/glyphs.xml
prince: loading font: /usr/share/fonts/truetype/msttcorefonts/times.ttf
prince: warning: no font for Mathematical Operators character U+2200, fallback to U+2BD1 ⯑
prince: loading font: /usr/local/lib/prince/style/../fonts/prince-fallback.ttf
prince: used font: PrinceFallback, Regular
prince: used font: Times New Roman, Regular
prince: loading font: /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman_Italic.ttf
prince: used font: Times New Roman, Italic
prince: warning: no font for Mathematical Operators character U+2208, fallback to U+2BD1 ⯑
prince: warning: no font for Arrows character U+21D2, fallback to U+2BD1 ⯑
prince: warning: no font for Mathematical Operators character U+2227, fallback to U+2BD1 ⯑
prince: Converting document...
prince: loading font: /usr/share/fonts/truetype/msttcorefonts/Arial_Bold.ttf
prince: used font: Arial, Bold
prince: loading font: /usr/share/fonts/truetype/msttcorefonts/Courier_New.ttf
prince: used font: Courier New, Regular
prince: loading font: /usr/share/fonts/truetype/msttcorefonts/couri.ttf
prince: used font: Courier New, Italic
prince: loading font: /usr/share/fonts/truetype/msttcorefonts/Courier_New_Bold.ttf
prince: used font: Courier New, Bold
prince: loading font: /usr/share/fonts/truetype/msttcorefonts/Times_New_Roman_Bold.ttf
prince: used font: Times New Roman, Bold
prince: Finished: success

I had previously been able to do the convertion correctly on a different system (sadly I no longer has access to that system, but I believe the msttcore fonts was what solved the issue before), but it seems now even with the msttcorefonts it's having trouble displaying math characters? Is there a font I'm missing and should download/install?

OpenSymbol or DejaVu Sans should help.

Thanks, installing dejavu fixes it!