Incoming call handling breaks upon losing focus when "always use full screen for notifications" flag turned on in app settings, other breakage follows

[Vincent Meadows]

Checklist

• I can reproduce the bug with the latest version given here.
• I made sure that there are no existing issues - open or closed - to which I could contribute my information.
• I made sure that there are no existing discussions - open or closed - to which I could contribute my information.
• I have read the FAQs inside the app (Menu -> About -> FAQs) and my problem isn't listed.
• I have taken the time to fill in all the required details. I understand that the bug report will be dismissed otherwise.
• This issue contains only one bug.
• I have read and understood the contribution guidelines.

Affected app version

1.1.1

Affected Android/Custom ROM version

Android 14 / LineageOS 21, Feb 2024 OS patch level, Mar 2024 vendor patch level

Affected device model

Google Pixel 7 Pro

How did you install the app?

F-Droid / IzzyOnDroid

Steps to reproduce the bug

1. Ensure app is set as default phone app, no other phone apps available to take over in case of breakage.
2. Ensure "always use full screen for notifications" toggle is on inside application settings.
3. When an incoming call arrives, either back out of the screen using system gestures or have any other application produce a heads-up banner notification that interrupts the full-screen UI.
4. Attempt to receive a second incoming call.
5. Profit? In-call UI never shows up again, incoming call notifications completely break and no longer work, and even if you answer the call, the app never allows you to know if it acutally answered or not; the only way to tell is if you're actually able to speak with the person on the other side.
6. Force-stop (not just clear from recent apps menu, but ACTUALLY force stop) and reopen the app, or restart device.
7. App works fine until step 3 happens again.

Expected behavior

The app should be able to resiliently handle any form of interruption to its full-screen UI for incoming calls, including other apps' notification banners popping up, or system gestures backing out of, or killing, the call answer screen. It should also still be able to show the in-call UI if answered another way, and have a persistent "call in progress" notification show in your status bar if answered successfully that, when clicked, takes you to the in-call UI directly.

Actual behavior

None of the above happens; the whole incoming call and in-call UI areas of the app are completely broken until a force-stop of the application, whether you just kill the app itself or restart your device. It MUST leave RAM before it resumes working normally again, at which point it will immediately break upon Step 3 of reproduction happens again. I'm not 100% sure if Step 2 is required to make the break occur either, but that setting was toggled on for my installation.

Screenshots/Screen recordings

I have none available at this point in time. I did not grab any during the breakages as whilst answering a call, I had not thought to do so on any occasion it occurred.

Additional information

My device is rooted, but no hooks of any variety are used on the application in question whatsoever. As far as this app sees, everything should be completely vanilla LineageOS with standard Google Apps installed, minus the dialer being disabled.