It happened, and I dismissed it, but then thought it should be something to mention.
It didn't take much effort to invoke the problem again.
This is the screen as it was:
I then drag a
function node onto the screen. NOTHING ELSE
And this is what I see:
How did those two connections happen?
Raspberry Pi 2 Model B Rev 1.1 PRETTY_NAME="Raspbian GNU/Linux 9 (stretch)" NAME="Raspbian GNU/Linux" VERSION_ID="9" VERSION="9 (stretch)" VERSION_CODENAME=stretch ID=raspbian ID_LIKE=debian HOME_URL="http://www.raspbian.org/" SUPPORT_URL="http://www.raspbian.org/RaspbianForums" BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs" Raspberry Pi reference 2017-09-07 Generated using pi-gen, https://github.com/RPi-Distro/pi-gen, 496e41575eeb9fa13f394ffb407b7bc1d00b21c2, stage5 Linux BedPi 4.19.66-v7+ #1253 SMP Thu Aug 15 11:49:46 BST 2019 armv7l GNU/Linux