Crash in MySerializedProperty

[Tommigun1980]

When multi-selecting objects in the editor and editing a list property in them, the following crash happens:

NullReferenceException: Object reference not set to an instance of an object
MyBox.EditorTools.MySerializedProperty.AsStringValue (UnityEditor.SerializedProperty property) (at Library/PackageCache/com.domybest.mybox@701527564a/Extensions/EditorExtensions/MySerializedProperty.cs:116)
MyBox.Internal.ConditionalUtility.IsConditionMatch (UnityEditor.SerializedProperty property, System.Boolean inverse, System.String[] compareAgainst) (at Library/PackageCache/com.domybest.mybox@701527564a/Tools/Internal/ConditionalUtility.cs:61)
MyBox.Internal.ConditionalUtility.IsPropertyConditionMatch (UnityEditor.SerializedProperty property, MyBox.Internal.ConditionalData condition) (at Library/PackageCache/com.domybest.mybox@701527564a/Tools/Internal/ConditionalUtility.cs:39)
MyBox.Internal.ConditionalFieldAttributeDrawer.GetPropertyHeight (UnityEditor.SerializedProperty property, UnityEngine.GUIContent label) (at Library/PackageCache/com.domybest.mybox@701527564a/Attributes/ConditionalFieldAttribute.cs:50)
UnityEditor.PropertyDrawer.GetPropertyHeightSafe (UnityEditor.SerializedProperty property, UnityEngine.GUIContent label) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyDrawer.cs:43)
UnityEditor.PropertyHandler.GetHeight (UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:312)
UnityEditor.PropertyHandler.GetHeight (UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:351)
UnityEditorInternal.ReorderableList.TryOverrideElementHeightWithPropertyDrawer (UnityEditor.SerializedProperty property, System.Single& height) (at /Users/bokken/build/output/unity/unity/Editor/Mono/GUI/ReorderableList.cs:550)
UnityEditorInternal.ReorderableList.CacheIfNeeded () (at /Users/bokken/build/output/unity/unity/Editor/Mono/GUI/ReorderableList.cs:581)
UnityEditorInternal.ReorderableList.GetListElementHeight () (at /Users/bokken/build/output/unity/unity/Editor/Mono/GUI/ReorderableList.cs:791)
UnityEditorInternal.ReorderableList.DoList (UnityEngine.Rect rect, UnityEngine.Rect visibleRect) (at /Users/bokken/build/output/unity/unity/Editor/Mono/GUI/ReorderableList.cs:763)
UnityEditorInternal.ReorderableListWrapper.DrawChildren (UnityEngine.Rect listRect, UnityEngine.Rect headerRect, UnityEngine.Rect sizeRect, UnityEngine.Rect visibleRect, UnityEngine.EventType previousEvent) (at /Users/bokken/build/output/unity/unity/Editor/Mono/Inspector/ReorderableListWrapper.cs:210)
UnityEditorInternal.ReorderableListWrapper.Draw (UnityEngine.GUIContent label, UnityEngine.Rect r, UnityEngine.Rect visibleArea, System.String tooltip, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/Inspector/ReorderableListWrapper.cs:164)
UnityEditor.PropertyHandler.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren, UnityEngine.Rect visibleArea) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:222)
UnityEditor.PropertyHandler.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:141)
UnityEditor.EditorGUI.PropertyFieldInternal (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/EditorGUI.cs:7329)
UnityEditor.EditorGUI.PropertyField (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/EditorGUI.cs:8812)
MyBox.Internal.CollectionWrapperDrawer.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label) (at Library/PackageCache/com.domybest.mybox@701527564a/Types/CollectionWrapper.cs:40)
UnityEditor.PropertyDrawer.OnGUISafe (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyDrawer.cs:23)
UnityEditor.PropertyHandler.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren, UnityEngine.Rect visibleArea) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:180)
UnityEditor.PropertyHandler.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:141)
UnityEditor.PropertyHandler.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren, UnityEngine.Rect visibleArea) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:264)
UnityEditor.PropertyHandler.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:141)
UnityEditor.EditorGUI.PropertyFieldInternal (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/EditorGUI.cs:7329)
UnityEditor.EditorGUI.PropertyField (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/EditorGUI.cs:8812)
MyBox.Internal.ConditionalFieldAttributeDrawer.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label) (at Library/PackageCache/com.domybest.mybox@701527564a/Attributes/ConditionalFieldAttribute.cs:61)
UnityEditor.PropertyDrawer.OnGUISafe (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyDrawer.cs:23)
UnityEditor.PropertyHandler.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren, UnityEngine.Rect visibleArea) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:180)
UnityEditor.PropertyHandler.OnGUI (UnityEngine.Rect position, UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:141)
UnityEditor.PropertyHandler.OnGUILayout (UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren, UnityEngine.GUILayoutOption[] options) (at /Users/bokken/build/output/unity/unity/Editor/Mono/ScriptAttributeGUI/PropertyHandler.cs:294)
UnityEditor.EditorGUILayout.PropertyField (UnityEditor.SerializedProperty property, UnityEngine.GUIContent label, System.Boolean includeChildren, UnityEngine.GUILayoutOption[] options) (at /Users/bokken/build/output/unity/unity/Editor/Mono/EditorGUI.cs:11030)
UnityEditor.EditorGUILayout.PropertyField (UnityEditor.SerializedProperty property, System.Boolean includeChildren, UnityEngine.GUILayoutOption[] options) (at /Users/bokken/build/output/unity/unity/Editor/Mono/EditorGUI.cs:11024)
MyBox.Internal.FoldoutAttributeHandler.Body () (at Library/PackageCache/com.domybest.mybox@701527564a/Attributes/FoldoutAttribute.cs:105)
MyBox.Internal.FoldoutAttributeHandler.OnInspectorGUI () (at Library/PackageCache/com.domybest.mybox@701527564a/Attributes/FoldoutAttribute.cs:75)
MyBox.Internal.UnityObjectEditor.OnInspectorGUI () (at Library/PackageCache/com.domybest.mybox@701527564a/Tools/Internal/UnityObjectEditor.cs:34)
UnityEditor.UIElements.InspectorElement+<>c__DisplayClass71_0.<CreateIMGUIInspectorFromEditor>b__0 () (at /Users/bokken/build/output/unity/unity/Editor/Mono/UIElements/Inspector/InspectorElement.cs:685)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr, Boolean&) (at /Users/bokken/build/output/unity/unity/Modules/IMGUI/GUIUtility.cs:189)

I had several objects selected that had a list, set all of the list's sizes to 0 (this worked), and then tried to set them to 1 and this crash happens.