Did something change with regard to \definefontfamily recently. I have an old document where I use: \starttypescript[mainface] \definefontfamily[mainface][rm][Libertinus Serif][features=default] \definefontfamily[mainface][ss] [heros] [features=default] \definefontfamily[mainface][tt] [dejavu] [features=none, rscale=0.85] \definefontfamily[mainface][mm] [LibertinusMath] \stoptypescript \setupbodyfont[mainface,12pt] On the recent LMTX (2020.09.05) I get selectfont > the requested font 'Libertinus Serif' has no files for the 'tf' alternative, Latin Modern is used instead. selectfont > the requested font 'heros' has no files for the 'tf' alternative, Latin Modern is used instead. selectfont > the requested font 'dejavu' has no files for the 'tf' alternative, Latin Modern is used instead. selectfont > the requested font 'LibertinusMath' has no files for the 'tf' alternative, Latin Modern is used instead. I can find the fonts using mtxrun --script fonts. For example: $mtxrun --script fonts --list --pattern="LibertinusSerif" --all identifier familyname fontname filename subfont instances libertinusserif libertinusserif libertinusserif libertinusserif-regular.otf libertinusserifdisplaynormal libertinusserifdisplay libertinusserifdisplay libertinusserifdisplay-regular.otf libertinusserifdisplayregular libertinusserifdisplay libertinusserifdisplay libertinusserifdisplay-regular.otf libertinusserifinitialsnormal libertinusserifinitials libertinusserifinitials libertinusserifinitials-regular.otf libertinusserifinitialsregular libertinusserifinitials libertinusserifinitials libertinusserifinitials-regular.otf libertinusserifnormal libertinusserif libertinusserifitalic libertinusserif-italic.otf libertinusserifregular libertinusserif libertinusserif libertinusserif-regular.otf and similar for the other fonts. Any idea on what is going on and how to debug. Thanks, Aditya