Ever 10 frames in a series of 30 subs. There was a previous run of 10 subs so I'm already starting with a bit of memory load.
stellarmate@stellarmate:~$ ps auxww | grep kstars
Start: stellar+ 1301 1.0 36.9 2959744 1372704 ? SLl 11:20 6:49 /usr/bin/kstars --paused
10 subs: stellar+ 1301 1.1 45.5 3280028 1691824 ? SLl 11:20 7:18 /usr/bin/kstars --paused
20 subs: stellar+ 1301 1.2 54.1 3600308 2012224 ? SLl 11:20 7:43 /usr/bin/kstars --paused
30 subs: stellar+ 1301 1.2 62.4 3920592 2317312 ? SLl 11:20 8:07 /usr/bin/kstars --paused
stellarmate@stellarmate:~$ sudo dpkg --list | grep kstars
ii kstars-bleeding 6:3.3.9+202001011609~ubuntu18.04.1 arm64 desktop planetarium for KDE
ii kstars-bleeding-data 6:3.3.9+202001011609~ubuntu18.04.1 all data files for KStars desktop planetarium
ii kstars-bleeding-dbg 6:3.3.9+202001011609~ubuntu18.04.1 arm64 debug information for the desktop planetarium for KDE
stellarmate@stellarmate:~$ sudo dpkg --list | grep qhy
ii indi-qhy 2.6~202001021211~ubuntu18.04.1 arm64 INDI QHY Driver. This driver is compatible with any INDI client such as KStars or Xephem.
ii libqhy 6.0.5+unstable~201912300954~ubuntu18.04.1 arm64 libqhy provide libraries to access and control QHY CCDs and Filter Wheels.
Disconnecting the gear and stopping the server made no difference of course.