How to reproduce:
1. Create a new project
2. Load the attached "IN-132417_Layout.wlt" layout (Window -> Layouts -> Load Layout from File)
3. Install the com.unity.mobile.notifications package (Window → Package Manager)
4. Enter and exit Play Mode
5. Select a GameObject
6. Undo the action (Ctrl/Cmd + Z)
7. Observe the Console

Actual result: Undo action throws “SerializedObject target has been destroyed.”
Expected result: No errors are logged

Reproducible with: 2.0.0 (6000.0.0b11), 2.4.2 (6000.0.0b11, 6000.0.66f1, 6000.3.6f1, 6000.4.0a3, 6000.4.0b7)
Not reproducible with: 2.0.0 (2023.3.0b10), 2.4.2 (2023.3.0b10, 6000.5.0a6)
Fixed in: 2.4.2 (6000.5.0a1)

Reproducible on: MacOS Sequoia 15.7.3 (M1 Max)
Not reproducible on: No other environments tested

Note: If you can’t reproduce the issue after the steps, try creating a new scene and repeating from step 4