Firmware Installation Process Issue
I would recommend all of us who do not want to waste time fighting with the firmware installation issue to switch to STM32CubeIDE.
STM32CubeIDE is introduced by ST as their official IDE. It is presented as the line of Atollic TrueStudio, after Atollic was acquired by ST. It is Eclipse-based as well and looks very solid-made.
It seems that the partnership between ST and ac6 is no more alive, therefore we experience problems with support.