diff -r d9a54c4c9da9 -r 3cc73d00553c src/Pure/Thy/export.scala
--- a/src/Pure/Thy/export.scala	Sat Nov 28 20:18:29 2020 +0100
+++ b/src/Pure/Thy/export.scala	Sat Nov 28 21:56:24 2020 +0100
@@ -372,7 +372,8 @@
 
   val default_export_dir: Path = Path.explode("export")
 
-  val isabelle_tool = Isabelle_Tool("export", "retrieve theory exports", args =>
+  val isabelle_tool = Isabelle_Tool("export", "retrieve theory exports",
+    Scala_Project.here, args =>
   {
     /* arguments */