The Errata sheet for STM32G030x6/x8, ES0486 - Rev 6, states in chapter 2.2.9:
After connecting the debug interface and until the device power-down, the boot source upon reset or wakeup from a low-power mode is determined by the PA14-BOOT0 pin level before connecting the debug interface (stored by the device), as opposed to the actual PA14-BOOT0 pin level. The device power-up restores the operation of the PA14-BOOT0 pin as direct boot source selector.
But this also applies to the empty check: if the debug interface is connected, the empty check is only updated on device power-up (reset is not sufficient).
So, if you program an empty device with the STM32CubeIDE in order to debug the software, you need to stop the first debugging session, perform a power cycle and start the next debugging session. Otherwise, the µC will keep executing the bootloader and debugging will fail with “Break at address 0x1f… with no debug information available, or outside of program code”.
