Backspace key doesn't work on AOSP-based keyboards

[0xC0ffee1]

When using a custom keyboard (AOSP based) on an Android device (tested on Android 14), the backspace key does not function as expected. This issue does not occur when using Gboard.

Steps to reproduce:

1. Run the mock.dart example on any android device (Tested on Android 14, both physical and emulated).
2. Switch to an AOSP-based keyboard (tested on OpenBoard, HeliBoard, and GrapheneOS stock keyboard).
3. Attempt to use the backspace key.

Expected Result:
The backspace key should function correctly, deleting characters as expected.

Actual Result:
The backspace key does not work when using custom keyboards.

Flutter: Channel stable, 3.22.3

Demo:
demo.webm