--- a/DoWhatIMeanSupport.st	Wed Oct 02 02:24:04 2019 +0200
+++ b/DoWhatIMeanSupport.st	Sun Oct 06 17:43:47 2019 +0200
@@ -1679,13 +1679,15 @@
             ].
             actions := actions asOrderedCollection.
             listOfSuggestions doWithIndex:[:suggestion :idx |
-                (suggestions includes:suggestion) ifFalse:[
-                    (selectorEndsWithColon not or:[suggestion endsWith:$:]) ifTrue:[
-                        suggestions add:suggestion.
-                        listOfActionsOrBlock isBlock ifTrue:[
-                            actions add:listOfActionsOrBlock.
-                        ] ifFalse:[
-                            actions add:(listOfActionsOrBlock at:idx).
+                suggestion notNil ifTrue:[
+                    (suggestions includes:suggestion) ifFalse:[
+                        (selectorEndsWithColon not or:[suggestion endsWith:$:]) ifTrue:[
+                            suggestions add:suggestion.
+                            listOfActionsOrBlock isBlock ifTrue:[
+                                actions add:listOfActionsOrBlock.
+                            ] ifFalse:[
+                                actions add:(listOfActionsOrBlock at:idx).
+                            ]
                         ]
                     ]
                 ]
@@ -1885,6 +1887,7 @@
 
     addSymbol :=
         [:aSymbol |
+            aSymbol isNil ifTrue:[self halt].
             (aSymbol startsWith:sym) ifTrue:[
                 (aSymbol = sym) ifFalse:[
                     possibleCompletions add:aSymbol