Heating slighly = 50°C aprox, more than ~108MHz was unstable.
200MHz didn't work at all, I just knew it was running at that speed by checking the MCO output.
Max realistic working speed was 96MHz, I blasted it with hot air and it kept working at burning temperatures.
You have a video in YouTube testing up to 7V, I don't think the chip is different.
You can see how the current quickly increases over 4V, first indication of "not made for 5V".
The current meter in that PSU seems unreliable, as the HK32F030M already consumes about 4mA at 3.3V, with nothing else.
That board has several leds, yet measures "0.000".
So it seems to me the current consumption at 5v is much higher than shown there.
No idea about supporting plataformio, neither I use it, I patched STM32 CubeIDE and use DIY J-Link.
Anyways my attention is now in the Puya PY32F002A

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