pending-del doesn't fully work

Hi, I switched to 21.2.19 recently. The only thing not working as before is pending-del mode. When I select a region, and try to replace it by click "paste" key, it just inserts it not replace it. And if I type something with keyboard, it replaces. It ususally works in old version with both ways. Please advice. Thanks. Midas -- *================================================================* Midas Lin Email : midas(a)cadence.com DSM Business Unit Tel : (408) 428-5027 Cadence Design Systems, Inc. Fax : (408) 428-5959 *================================================================*