diff --git a/ide/sourceeditor.pp b/ide/sourceeditor.pp
index 9f8b030cc1..9aed436cd3 100644
--- a/ide/sourceeditor.pp
+++ b/ide/sourceeditor.pp
@@ -6968,6 +6968,7 @@ Begin
     debugln('[TSourceNotebook.CreateNotebook] C');
     {$ENDIF}
     EditorOpts.ApplyTabFontSettingsTo(FNotebook);
+    TabStop := false;
     Align := alClient;
     APage:=TTabSheet.Create(FNotebook);
     APage.Caption:='unit1';