"Unlock the screen" setting switches off by itself

On version 4.31.3 the setting to unlock the screen (in "Controlling" -> "Display") switches off by itself. Steps to reproduce are:

1/ switch "Unlock the screen" on

2/ go back to main view, leave the app, use main display button - a couple of times! Usually doing 3-4 of these activities one after the other caused the issue

3/ notice that screen starts locking at one point. The setting "Unlock the screen" is now off

I'm 100% sure this wasn't the case with versions at and prior to 4.31.1, not sure about 4.31.2. The issue just started happening sometime in the past month.