Helios 300 activates disabled adaptive brightness (Intel's DPST) when unplugging the power cord

Already tried that too. I've edited every power plan I could find and disabled any display-related technology in every plan even those that aren't active - didn't help. The strangest thing about this is that those settings don't change when it happens. I have an old notebook/tablet-hybrid from ASUS which also has Intel Graphics and when it updated itself to the latest version of Windows, adaptive brightness enabled itself too, but... I could see it set to "Enabled" in the Intel panel there and disabling it got rid of the problem permanently.

Here in the Acer laptop it always stays on disabled, yet in reality it's enabled. It sounds like it could be some other setting somewhere, but because if I enable and disable it in the Intel graphics settings and it helps, I'm sure it has to do something with those settings. Granted, maybe some Acer software loads a different Intel graphics profile in the background, but my current profile, aside from having the dimming disabled also has some screen calibration set up (minor adjustment - blue channel set to -6%) and when this happens, the colors don't change so it can't be a reset of the whole profile otherwise the white point would also get more blue.

Option 1 - yes, this of course works... until I plug the laptop in and unplug it again. That's the whole problem, then I have to set it to enable and then disable again and it works again... until I plug it in and unplug it and so on.

Option 2 - tried that already during the initial Googling session - didn't help either.

Option 3 - haven't tried it yet, but... wouldn't this just reset everything, make me set it up as it is now again? The adaptive brightness part is already done - I went to those advanced settings, went through everything there, set it all up to most performance, no power saving modes etc.

Technically, every settings is set correctly and it all works correctly... until a switch from "plugged in" to "on battery" happens. BTW, in case I didn't make it clear, once I enable and disable the Intel graphics settings while I'm on battery, then it will still keep working fine while on battery, even after full shutdown and reboot, the only trigger for this issue is the switch from plugged in to battery so whenever I need to charge it, I must do the "turn it on and back off again" for the Intel power setting. What happens during the switch to battery - no idea.

This isn't happening on boot. Let me explain this again, in 3 simple steps:

STEP 1 - I'm using the laptop on battery, the screen is NOT getting dimmed, everything works fine. No problems.

STEP 2 - I plug in the power cord so now I'm powering the laptop from the grid. The screen still isn't dimming itself, everything's fine.

STEP 3 - I pull the power cord out... and now the screen starts to dim itself immediately. There's no reboot in between, I'm not even closing the lid, the laptop isn't waking up from sleep. Just pulling the power cord out immediately activates the dimming.

At this point I have to go to Intel's control panel, turn the dimming on (cause technically it's still disabled there), then turn it off and now I'm back at step 1 where everything works fine... until I connect and disconnect the power cord and I can reproduce this multiple times even during the same session, while the laptop is on.

Again, either it's really a bug with Intel's drivers and they have to fix it, or Acer implemented some power saving solution somewhere and it ignores Intel's settings which is why it always reactivates this feature when I switch from being plugged in to battery.