HandBrake segfaults

HandBrake always worked fine until today. Now it starts and I can set up a transcode, and that starts and spins the drive, then it closes. Running from Konsole I get:

howard@T61-oS154:~> /usr/bin/HandBrakeGUI
libdvdnav: DVD Title: ONE_FLEW_OVER_THE_CUCKOOS_NEST  
libdvdnav: DVD Serial Number: 2cd61cc4
libdvdnav: DVD Title (Alternative): 
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
libdvdnav: DVD Title: ONE_FLEW_OVER_THE_CUCKOOS_NEST  
libdvdnav: DVD Serial Number: 2cd61cc4
libdvdnav: DVD Title (Alternative): 
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
libdvdnav: DVD Title: ONE_FLEW_OVER_THE_CUCKOOS_NEST  
libdvdnav: DVD Serial Number: 2cd61cc4
libdvdnav: DVD Title (Alternative): 
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
libdvdnav: DVD disk reports itself with Region mask 0x00f00000. Regions: 01 02 03 04
Segmentation fault (core dumped)
howard@T61-oS154:~> 

The same behavior with several DVDs and two different drives. HandBrake works fine on another system with exactly the same settings.
What is the problem?

Have you installed HandBrake as a Flatpak from the HandBrake Downloads site?
<https://handbrake.fr/downloads.php>