LiveDisplay settings cannot be changed

• /e/ version: 0.9-p-2020042851769-test-FP3
• Device model: FP3
• When it started to occur: right from the beginning
• Reproducible with the last /e/ version: yes
• Reproducible with LineageOS: no

Summary

LiveDisplay settings take no effect

• The device is unusable
• The bug is the source of a data loss or a big waste of time
• The bug concerns a third party app
• The bug concerns security
• The bug concerns privacy

The problem

Steps to reproduce

Go to Settings > Display > LiveDisplay > Display mode and select any of the options besides "Off"

What is the current behavior?

Whatever I select, it takes no effect and when I leave the settings and come back again it's always back to "Off".

What is the expected correct behavior?

The changed option is saved and takes effect, e.g. colouring the display slightly red in the evening.

Technical informations

Possible fixes

The same error occured in Lineage OS 17.1 for the FP2 and there the fix was https://review.lineageos.org/c/LineageOS/android_device_fairphone_FP2/+/272151