Dell XPS 13 9370: screen brightness changes based on window contents

On my new Dell XPS 13 9370, it seems that the display backlight brightness is adjusted based on the brightness of whatever's on the screen.

For example, say I have Sublime Text open with a dark theme, and I click on the file menu. The menu dropdown has a light background, and this is enough to darken the entire screen. Moving the selection over to the "Selection" menu causes the screen to lighten back up again, because this menu is apparently small enough for it not to count.

You can see the effect here, as I switch between a larger and smaller menu:

I find this feature unpleasantly jarring as I navigate through menus and similar. Is it possible to turn it off?

In case it is relevant, my system specs are as follows:

• Dell XPS 13 (9370)
• Debian Linux (sid)
• Cinnamon DE

According to Dell_Guy on the Dell.com community forums:

You can fix this by disabling Dynamic Brightness Control under the BIOS settings.

Original Quote from Link:

You can go into BIOS settings (hit F2 as you are restarting your computer) - and DISABLE Dynamic Brightness Control in the display options. I don't know if you need to update the laptop to the LATEST bios to have this option (I did the update).