Automatic adaptive brightness / contrast

Hi all,

On my XPS 15 7590 it is seemingly impossible to switch off the adaptive brightness that happens when not connected to a power source - I cannot find this option anywhere. Whenever I switch tabs from a darker page to a brighter page, the contrast dramatically changes. This makes photo/video editing near impossible, is very frustrating when watching videos or opening a dark-mode program (eg. Spotify)

• I cannot find the BIOS EcoSystem power options, they have been since removed in an update.
• Turned off automatic brightness / contrast in Intel Graphics Command Center under the Display > Power settings.
• The adaptive brightness in Windows 10 Power Options have been removed.
• Turned off Windows 10 HDR Colour settings

I really hope someone out there has found a solution to this problem as it makes my display unusable for work when not plugged into power.

Kind regards,
Adomas