New bug introduced in fw 2.4 regarding motion & backlight

Hi!

Got my Fenix 5sapphire today and one of the coolest features was that I could turn on backgroundlight based on motion. this is same feature the Fitbit has.

If I move my hand in a certain pattern, (like you do when you want to check out what time it is) the backlight turn on automatically

This worked great on Fw 2.00, but I updated to fw 2.4 and now the feature do not work anymore
I tried to toggle the setting on/off but no luck

Do anyone else got this to work on fw 2.4 ? Can I downgrade back to 2.0?
Garmin has great hardware but must have the worst betatesters.