diff --git a/components/synedit/syngutterlineoverview.pp b/components/synedit/syngutterlineoverview.pp
index 9edbaba3bb..3d7a537a44 100644
--- a/components/synedit/syngutterlineoverview.pp
+++ b/components/synedit/syngutterlineoverview.pp
@@ -1196,6 +1196,7 @@ end;
 
 destructor TSynGutterLOvProviderBookmarks.Destroy;
 begin
+  TSynEditStringList(TextBuffer).RemoveHanlders(self);
   TSynEdit(SynEdit).Marks.UnRegisterChangeHandler({$IFDEF FPC}@{$ENDIF}DoMarkChange);
   inherited Destroy;
 end;