iOS App stuck on black screen after launch (Flutter 3.35.6) – works fine on Flutter 3.24.5

After installing the app from App Store or TestFlight, when the user opens the app and then force-kills it multiple times, the app sometimes gets permanently stuck on a black screen at launch.

This issue does NOT happen on Flutter 3.24.5 — works perfectly on all tested iOS devices. The problem started only after migrating to Flutter 3.35.6. This issue happens only in real production installs (App Store / TestFlight). It does not reproduce in Debug mode or through Xcode run / Android Studio run.

Expected behavior App should show native splash → render Flutter UI normally.

Actual behavior Sometimes after killing the app repeatedly: Native splash shows briefly → then screen turns completely black and stays stuck

Steps to Reproduce: Install the app from App Store or TestFlight Launch the app Force-kill the app using app switcher Repeat launch + kill multiple times After 3–7 attempts, app gets stuck on black screen on launch

Is this a known issue with the latest Flutter iOS engine? Could this be related to Flutter engine warm-up, pre-warming isolates, or native splash transition? Is there any recommended fix or workaround on iOS side? (e.g., ApplicationDidBecomeActive callbacks, UIWindow setup, GPU thread rendering flush, etc.)

iOS App stuck on black screen after launch (Flutter 3.35.6) – works fine on Flutter 3.24.5
 
 
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