--- a/AbstractOperatingSystem.st	Tue Jan 21 16:06:48 2020 +0100
+++ b/AbstractOperatingSystem.st	Tue Jan 21 16:07:09 2020 +0100
@@ -730,7 +730,7 @@
         ].
     ].
     openCommand notEmptyOrNil ifTrue:[
-        (openCommand includesSubString:'%1') ifTrue:[
+        (openCommand includesString:'%1') ifTrue:[
             openCommand := openCommand bindWith:aFilenameOrString asString.
         ] ifFalse:[
             openCommand := openCommand, ' "', aFilenameOrString asString, '"'.