Editor hangs when trying to open prefab with TMP content

Unity Engine
1

Hello,

The Editor hangs when I try to open a prefab from script. I found the following in the log file.

MissingComponentException: There is no ‘RectTransform’ attached to the “Missing Prefab (Dummy)” game object, but a script is trying to access it.
You probably need to add a RectTransform to the game object “Missing Prefab (Dummy)”. Or your script needs to check if the component is attached before using it.
at (wrapper managed-to-native) UnityEngine.RectTransform:set_sizeDelta_Injected (UnityEngine.Vector2&)
at UnityEngine.RectTransform.set_sizeDelta (Vector2 value) [0x00000] in :0
at TMPro.TMP_Text.LoadDefaultSettings () [0x00070] in D:\blah\Library\PackageCache\com.unity.textmeshpro@1.3.0\Scripts\Runtime\TMP_Text.cs:5407
at TMPro.TextMeshProUGUI.Awake () [0x000df] in D:\blah\Library\PackageCache\com.unity.textmeshpro@1.3.0\Scripts\Runtime\TMPro_UGUI_Private.cs:112
UnityEditor.SceneManagement.EditorSceneManager:OpenPreviewScene_Injected(String, Scene&)
UnityEditor.SceneManagement.EditorSceneManager:OpenPreviewScene(String)
UnityEditor.PrefabUtility:LoadPrefabContents(String) (at C:\buildslave\unity\build\Editor\Mono\Prefabs\PrefabUtility.cs:1637)

It’s unclear to me what is wrong with the prefab, and I can’t tell, because I can’t open it.

Any help would be appreciated
Thank you

2

What version of Unity are you using?

Did you just upgrade to a newer version of Unity and this issue is now occurring?

3

Unity 2018.4.0f1
No, I did not just upgrade.

It took a while. I had to dig through the log file. But, I did finally find a name of the prefab. It was bad content. I don’t know how, but it had a bunch of missing child GameObjects.

So, I am now unstuck.

That being said, it was a pretty nasty process to track down, and it seems like the Unity Editor shouldn’t hang in this case.

Thank you