Hello, > Replacing certain symbols in a math font with a text font is very easy with the fallback > mechanism and the \definefallbackfamily command makes things even simpler. Thank you for your answer. The command \definefallbackfamily seems not to be a typescript-level command. Let us try \definefontfallback. Let us consider the statememt: \definefontfallback [BaskervaldOverPagella] [file:BaskervaldADFStd-Italic] [0x1D44E-0x1D467] [\check=yes,force=yes] I understand it as: “Replace the glyphs 0x1D44E-0x1D467 (mathematical a-z) of the source font with the glyphs from Baskervald italic having the same code.” But how do you map 0x1D44E-0x1D467 of the source font to 0x61-0x7a. How do you say: “Replace the glyphs 0x1D44E-0x1D467 (mathematical a-z) of the source font with the glyphs 0x61-0x7a (text a-z) from Baskervald italic”? For example something like: \definefontfallback [BaskervaldOverPagella] [file:BaskervaldADFStd-Italic] [0x1D44E-0x1D467] [0x61-0x7a] [\check=yes,force=yes] Other question: What do check, force and offset means? Thank you. Best regards, Joas.