While working on getting in-circuit debugging tested for the STM32 I notice that every time I restart the IDE the Board setting is defaulting to the Arduino Zero instead of the STM32F1 I'd selected and saved before exiting. Other settings related to the STM32 seem to restore fine once I change the Board.
Also, in order to upload code using the STM32CubeProgrammer option the path to the programmer bin direction must be in the env path, ie it's not set in the IDE anywhere. So I start the IDE like this:
PATH=$STM32CubeProgPATH/bin:$PATH ./arduino-ide_2.0.3_Linux_64bit.AppImage
I'd be happy installing a local copy of the dev branch if that'd be helpful.