1) Create a new StringTable or AssetTable for 1 or more locales.

2) Add 2 new Entries,

3) Click the Metadata button for the 2nd entry on one of the languages.

4) A NullReferenceException will be thrown.

NullReferenceException: Object reference not set to an instance of an object
UnityEditor.Localization.UI.MetadataCollectionField.GetPropertyHeight (UnityEditor.SerializedProperty property, UnityEngine.GUIContent label) (at C:/Unity/Packages/com.unity.localization/Packages/com.unity.localization/Editor/UI/Metadata/MetadataCollectionField.cs:127)
_UnityEditor.Localization.UI.TableEntrySelected+<>c__DisplayClass10_0.<CreateEditor>b__3 () (at C:/Unity/Packages/com.unity.localization/Packages/com.unity.localization/Editor/UI/Tables/TableEntrySelected.cs:75)_
UnityEngine.UIElements.IMGUIContainer.DoOnGUI (UnityEngine.Event evt, UnityEngine.Matrix4x4 parentTransform, UnityEngine.Rect clippingRect, System.Boolean isComputingLayout, UnityEngine.Rect layoutSize, System.Boolean canAffectFocus) (at <a6a3aac9b47844afbb8dcc407683ae01>:0)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)