While I don't currently have a link, depending on which model you have, CABC (Content Adaptive Brightness Control) can be disable officially, as well as unofficially.
I have an XPS 13 9350 with a 1080P matte display, with CABC disabled through the display firmware version hack -- I completely forget the steps though, and it appears as Dell has released a version of the FHD [0] but I don't plan on reverting to the proper firmware just to patch it out again.
I have an XPS 13 9350 with a 1080P matte display, with CABC disabled through the display firmware version hack -- I completely forget the steps though, and it appears as Dell has released a version of the FHD [0] but I don't plan on reverting to the proper firmware just to patch it out again.
0. https://www.dell.com/support/home/ca/en/cabsdt1/drivers/driv...
EDIT: https://github.com/advancingu/XPS13Linux/issues/2