Large Screen Device Exhibits Approximately 5-Second Restart Delay for Dual-Pane Interface Applications After Screen Orientation Change

Steps to Reproduce:

Device: Large screen device running Android 16

Test Application: Applications using Activity Embedding to implement dual-pane layouts (e.g., the sample application from the reference documentation) https://developer.android.google.cn/codelabs/large-screens/activity-embedding?hl=zh-cn#0

Steps:

Launch the dual-pane application (referred to as AA) in portrait mode. Startup is normal with no delay.

Press the Home button to send the application to the background.

Rotate the device to landscape mode.

Relaunch the application (by tapping its icon). A startup delay of approximately 5 seconds is observed.

Repeat the test: Landscape → Press Home to exit → Rotate to portrait mode → Relaunch. The same ~5-second delay occurs.

Scope of the Issue:

This problem occurs in all applications that use Activity Embedding to implement dual-pane interfaces.

It includes the official dual-pane sample application from the reference documentation.

Multiple third-party applications have reproduced the same phenomenon in the same scenario.

The delay only occurs during relaunch after a screen orientation change; the initial launch is normal.

Expected Behavior:

Regardless of the current screen orientation, the application should restart as quickly as it did on the initial launch, with no significant delay.

Actual Behavior:

When relaunching a dual-pane application after a screen orientation change, there is a startup delay of approximately 5 seconds, which affects user experience and application responsiveness.

Key Points of the Issue:

Only affects large screen devices (those supporting dual-pane layouts in both landscape and portrait).

Only occurs in applications that use Activity Embedding technology.

The delay is correlated with screen orientation changes.

The initial launch is normal; the issue only manifests during relaunch.