diff --git a/src/roster_window.py b/src/roster_window.py
index 3546bac94..0947de722 100644
--- a/src/roster_window.py
+++ b/src/roster_window.py
@@ -5507,7 +5507,7 @@ class RosterWindow:
 			elif contacts_transport != transport:
 				contacts_transport = False
 
-		if not contacts_transport:
+		if contacts_transport == False:
 			# they are not all from the same transport
 			invite_menuitem.set_sensitive(False)
 			return