I think that it's a critical bug, because it broke an app theme (start screens has a light theme, other screens has a dark theme).

I attached all videos and sample.

Prerequisites:

• App with at least 2 screens.
• Android 14/15

Affected build versions:

• AP1A.240405.002 (Pixel 7 Android 14)
• UP1A.231105.001.B2 (Pixel 5 Android 14)
• AP31.240322.020 (Emulator Android 15)
• UE1A.230829.036.A2 (Emulator Android 14)

Not affected build versions:

• TE1A.220922.012 (Emulator Android 13)

Reproduce steps:

1. Enable Dark Mode from a system settings
2. Add resizeableActivity=false in App manifest
3. Enable Dark Mode on a second screen for App with UiModeManager.setApplicationNightMode(UiModeManager.MODE_NIGHT_YES)
4. Hide App in dock from a first screen (swipe from down to up)
5. Disable Dark Mode from a system settings
6. Open App. Pay attention that App has a light theme, but we chose a dark before
7. Open second screen. App theme suddenly changes to dark for all screens, but on a first screen dark theme looks wrong

Why it's happening (my investigation):

When resizeableActivity is applied and set to false system decides to kill App process with log:

Killing 11810:com.example.darkmodebug/u0a193 (adj 700): resetConfig

I suggest that it's related to ActivityRecord logic. System executes restartProcessIfVisible() on 9052 line. It looks like Android incorrectly decides that it should kill App.

Expected behaviour:

It correctly works on Android 13, then it should be the same on Android 14 and more.