diff -r 2c0af1c2e723 -r ab66951166f3 src/Pure/Admin/other_isabelle.scala
--- a/src/Pure/Admin/other_isabelle.scala	Thu Nov 29 15:07:18 2018 +0100
+++ b/src/Pure/Admin/other_isabelle.scala	Thu Nov 29 15:17:51 2018 +0100
@@ -62,7 +62,7 @@
   val etc_preferences: Path = etc + Path.explode("preferences")
 
   def copy_fonts(target_dir: Path): Unit =
-    Isabelle_Fonts.make_entries(getenv = getenv(_), html = true).
+    Isabelle_Fonts.make_entries(getenv = getenv(_), hidden = true).
       foreach(entry => File.copy(entry.path, target_dir))