diff -r 75d14ac0547e -r 90bd7fc7fcc0 src/Doc/Isar_Ref/Symbols.thy
--- a/src/Doc/Isar_Ref/Symbols.thy	Sun Oct 03 21:29:34 2021 +0200
+++ b/src/Doc/Isar_Ref/Symbols.thy	Mon Oct 04 13:32:34 2021 +0200
@@ -37,4 +37,6 @@
   \end{center}
 \<close>
 
+external_file %invisible \<open>~~/lib/texinputs/isabellesym.sty\<close>
+
 end