Import Tk 8.6.8

library/menu.tcl

@@ -170,6 +170,7 @@ bind Menu <<NextLine>> {
 }
 bind Menu <KeyPress> {
     tk::TraverseWithinMenu %W %A
+    break
 }
 
 # The following bindings apply to all windows, and are used to
@@ -607,6 +608,10 @@ proc ::tk::MenuButtonDown menu {
     if {![winfo viewable $menu]} {
         return
     }
+    if {[$menu index active] eq "none"} {
+        set Priv(window) {}
+        return
+    }
     $menu postcascade active
     if {$Priv(postedMb) ne "" && [winfo viewable $Priv(postedMb)]} {
 	grab -global $Priv(postedMb)