Steps to reproduce:

1. Create and open an empty project.
2. Create a C# script (Assets > Create > C# Script).
3. Open the C# script in any code editor (to edit later).
4. Create an Audio Random Container (abbr. ARC) (Assets > Create > Audio > Audio Random Container).
5. Open the ARC asset by double-clicking on it. Make sure the ARC window is closed before opening it.
6. Dock the ARC window. Make sure that the ARC asset is highlighted in the Project window, so that it is showing in the ARC window.
7. Edit the C# script in any way you please.
8. Switch back to Unity with cmd+tab / ctrl+tab. This is to make sure the ARC window keeps showing the asset.
9. If no error appears in the console, repeat steps 5-8 until it does. Try to dock the window in various docking areas.

Actual results: A null reference error is thrown in the console

Expected results: No error is thrown in the console

Reproducible with versions: 2023.2.8f1, 2023.3.0b8

Can’t test with versions: 2022.3.X, 2021.3.X

Tested on (OS): MacOS (M1) Ventura 13.6.4

Stack trace

 
{code:java}
NullReferenceException: Object reference not set to an instance of an object
UnityEditor.AudioContainerWindow.UpdateTransportButtonStates () (at /Users/bokken/build/output/unity/unity/Editor/Mono/Audio/AudioContainerWindow.cs:404)
UnityEditor.AudioContainerWindow.BindAndTrackPreviewProperties () (at /Users/bokken/build/output/unity/unity/Editor/Mono/Audio/AudioContainerWindow.cs:369)
UnityEditor.AudioContainerWindow.BindAndTrackObjectAndProperties () (at /Users/bokken/build/output/unity/unity/Editor/Mono/Audio/AudioContainerWindow.cs:292)
UnityEditor.AudioContainerWindow.CreateGUI () (at /Users/bokken/build/output/unity/unity/Editor/Mono/Audio/AudioContainerWindow.cs:228)
UnityEditor.AudioContainerWindow.OnTargetChanged (System.Object sender, System.EventArgs e) (at /Users/bokken/build/output/unity/unity/Editor/Mono/Audio/AudioContainerWindow.cs:303)
UnityEditor.AudioContainerWindowState.UpdateTarget () (at /Users/bokken/build/output/unity/unity/Editor/Mono/Audio/AudioContainerWindowState.cs:168)
UnityEditor.AudioContainerWindowState.Resume () (at /Users/bokken/build/output/unity/unity/Editor/Mono/Audio/AudioContainerWindowState.cs:97)
UnityEditor.AudioContainerWindow.OnBecameVisible () (at /Users/bokken/build/output/unity/unity/Editor/Mono/Audio/AudioContainerWindow.cs:1209)
UnityEditor.HostView.RegisterSelectedPane (System.Boolean sendEvents) (at /Users/bokken/build/output/unity/unity/Editor/Mono/HostView.cs:609)
UnityEditor.HostView.OnEnable () (at /Users/bokken/build/output/unity/unity/Editor/Mono/HostView.cs:227)
UnityEditor.DockArea.OnEnable () (at /Users/bokken/build/output/unity/unity/Editor/Mono/GUI/DockArea.cs:177) {code}