--- .\original\mult-sys.mkiv	2020-07-23 23:03:23.513763700 +0400
+++ .\mult-sys.mkiv	2020-08-02 20:46:31.013921300 +0400
@@ -78,6 +78,7 @@
 \definesystemconstant {portuguese}     \definesystemconstant {pt}
 \definesystemconstant {romanian}       \definesystemconstant {ro}
 \definesystemconstant {russian}        \definesystemconstant {ru}
+\definesystemconstant {serbian}        \definesystemconstant {sr}
 \definesystemconstant {slovak}         \definesystemconstant {sk}
 \definesystemconstant {slovenian}      \definesystemconstant {sl}
 \definesystemconstant {spanish}        \definesystemconstant {es}
