--- a/SimpleView.st	Tue Jan 24 01:08:38 2017 +0100
+++ b/SimpleView.st	Tue Jan 24 12:18:59 2017 +0100
@@ -1536,11 +1536,16 @@
 
     |newDevice|
 
+    (XWorkstation notNil and:[ XWorkstation isLoaded ]) ifFalse:[
+        self warn:'Could not open display (no XWorkstation class)'.
+        ^ self
+    ].    
+    
     [
-	newDevice := XWorkstation newDispatchingFor:aScreenName.
+        newDevice := XWorkstation newDispatchingFor:aScreenName.
     ] on:Screen deviceOpenErrorSignal do:[:ex|
-	self warn:'Could not open display: ' , aScreenName.
-	^ self
+        self warn:'Could not open display: ' , aScreenName.
+        ^ self
     ].
     ^ (self onDevice:newDevice) open.