Editor crashes after packing when a tagged Sprite is used with a Sprite Mask

STEPS TO REPRO:
1. import Sprites into a new project
2. add a Packing Tag to one of the Sprites
3. with the tagged Sprite selected, right click in the Hierarchy and select 2D Object > Sprite Mask
4. a new Sprite Mask should be created in the Scene using the tagged Sprite
5. access the (Legacy) Sprite Packer window
6. click on Pack

The editor will crash to desktop after Sprites are packed.

*UPDATE*

This can also occur when packing a Sprite Atlas. If a Sprite in the Sprite Atlas is being used by a Sprite Mask, then the editor will crash after packing the Sprite Atlas.

========== OUTPUTING STACK TRACE ==================

0x00000001400483D4 (Unity) ThreadSharedObject<SharedMeshData>::ValidateObjectState
0x00000001418D98B8 (Unity) SpriteRenderData::AcquireReadOnlyData
0x00000001409861FE (Unity) SpriteMaskJobs::SpriteMaskSetupRenderNode
0x000000014098637B (Unity) SpriteMaskJobs::SpriteMaskPrepareRendererNodes<0>
0x0000000140CA9F19 (Unity) QueuePrepareIntegrateMainThreadObjects
0x0000000140CB848F (Unity) EndRenderQueueExtraction
0x0000000140C39247 (Unity) CullResults::GetOrCreateSharedRendererScene
0x0000000140C63830 (Unity) Camera::CustomRender
0x0000000140C64AEC (Unity) Camera::Render
0x0000000140C64D4B (Unity) Camera::Render
0x0000000140CA1390 (Unity) DoRenderScreenCamera
0x0000000140CBF5B6 (Unity) RenderManager::RenderCameras
0x00000001401F07B6 (Unity) RepaintController::RenderGameViewCameras
0x000000014176A131 (Unity) EditorGUIUtility_CUSTOM_INTERNAL_CALL_RenderGameViewCamerasInternal
0x0000000032270C64 (Mono JIT Code) (wrapper managed-to-native) UnityEditor.EditorGUIUtility:INTERNAL_CALL_RenderGameViewCamerasInternal (UnityEngine.RenderTexture,int,UnityEngine.Rect&,UnityEngine.Vector2&,bool)
0x0000000032270B34 (Mono JIT Code) [C:\buildslave\unity\build\artifacts\generated\common\editor\EditorGUIUtilityBindings.gen.cs:642] UnityEditor.EditorGUIUtility:RenderGameViewCamerasInternal (UnityEngine.RenderTexture,int,UnityEngine.Rect,UnityEngine.Vector2,bool)
0x000000003097BCE8 (Mono JIT Code) [C:\buildslave\unity\build\Editor\Mono\GameView\GameView.cs:747] UnityEditor.GameView:OnGUI ()
0x000000000B8D69E2 (Mono JIT Code) (wrapper runtime-invoke) object:runtime_invoke_void__this__ (object,intptr,intptr,intptr)
0x00007FFC5CE55B63 (mono) [c:\buildslave\mono\build\mono\mini\mini.c:4937] mono_jit_runtime_invoke
0x00007FFC5CDA872D (mono) [c:\buildslave\mono\build\mono\metadata\object.c:2623] mono_runtime_invoke
0x00007FFC5CDAEC3B (mono) [c:\buildslave\mono\build\mono\metadata\object.c:3838] mono_runtime_invoke_array
0x00007FFC5CD6D0F7 (mono) [c:\buildslave\mono\build\mono\metadata\icall.c:2750] ves_icall_InternalInvoke
0x000000000B8A0257 (Mono JIT Code) (wrapper managed-to-native) System.Reflection.MonoMethod:InternalInvoke (object,object[],System.Exception&)
0x000000000B89E3B2 (Mono JIT Code) [/Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:222] System.Reflection.MonoMethod:Invoke (object,System.Reflection.BindingFlags,System.Reflection.Binder,object[],System.Globalization.CultureInfo)
0x000000000B9828BF (Mono JIT Code) [/Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MethodBase.cs:115] System.Reflection.MethodBase:Invoke (object,object[])
0x000000002F703AA5 (Mono JIT Code) [C:\buildslave\unity\build\Editor\Mono\HostView.cs:272] UnityEditor.HostView:Invoke (string,object)
0x000000002F70394A (Mono JIT Code) [C:\buildslave\unity\build\Editor\Mono\HostView.cs:265] UnityEditor.HostView:Invoke (string)
0x0000000030978C13 (Mono JIT Code) [C:\buildslave\unity\build\Editor\Mono\HostView.cs:232] UnityEditor.HostView:InvokeOnGUI (UnityEngine.Rect)
0x0000000030959187 (Mono JIT Code) [C:\buildslave\unity\build\Editor\Mono\GUI\DockArea.cs:407] UnityEditor.DockArea:OldOnGUI ()
0x000000003094033F (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\IMGUIContainer.cs:115] UnityEngine.Experimental.UIElements.IMGUIContainer:DoOnGUI (UnityEngine.Event)
0x000000003093F744 (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\IMGUIContainer.cs:188] UnityEngine.Experimental.UIElements.IMGUIContainer:HandleEvent (UnityEngine.Event,UnityEngine.Experimental.UIElements.VisualElement)
0x00000000309CA207 (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\IMGUIContainer.cs:38] UnityEngine.Experimental.UIElements.IMGUIContainer:DoRepaint (UnityEngine.IStylePainter)
0x00000000309C5532 (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\Panel.cs:425] UnityEngine.Experimental.UIElements.Panel:PaintSubTree (UnityEngine.Event,UnityEngine.Experimental.UIElements.VisualElement,UnityEngine.Matrix4x4,UnityEngine.Rect)
0x00000000309C587C (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\Panel.cs:435] UnityEngine.Experimental.UIElements.Panel:PaintSubTree (UnityEngine.Event,UnityEngine.Experimental.UIElements.VisualElement,UnityEngine.Matrix4x4,UnityEngine.Rect)
0x00000000309C2198 (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\Panel.cs:450] UnityEngine.Experimental.UIElements.Panel:Repaint (UnityEngine.Event)
0x000000003092729F (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\UIElementsUtility.cs:178] UnityEngine.Experimental.UIElements.UIElementsUtility:DoDispatch (UnityEngine.Experimental.UIElements.BaseVisualElementPanel)
0x0000000030926F7B (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\UIElementsUtility.cs:71] UnityEngine.Experimental.UIElements.UIElementsUtility:ProcessEvent (int,intptr)
0x0000000030926A9D (Mono JIT Code) [C:\buildslave\unity\build\Runtime\IMGUI\Managed\GUIUtility.cs:186] UnityEngine.GUIUtility:ProcessEvent (int,intptr)
0x0000000030926C5E (Mono JIT Code) (wrapper runtime-invoke) <Module>:runtime_invoke_bool_int_intptr (object,intptr,intptr,intptr)
0x00007FFC5CE55B63 (mono) [c:\buildslave\mono\build\mono\mini\mini.c:4937] mono_jit_runtime_invoke
0x00007FFC5CDA872D (mono) [c:\buildslave\mono\build\mono\metadata\object.c:2623] mono_runtime_invoke
0x0000000141408F55 (Unity) scripting_method_invoke
0x0000000141401191 (Unity) ScriptingInvocation::Invoke
0x00000001401BE5DB (Unity) GUIView::ProcessRetainedMode
0x0000000140029B05 (Unity) GUIView::OnInputEvent
0x00000001401B19E3 (Unity) GUIView::ProcessInputEvent
0x0000000140006EC6 (Unity) GUIView::DoPaint
0x0000000140013790 (Unity) GUIView::RepaintAll
0x00000001401094F7 (Unity) Application::UpdateScene
0x000000014010D65F (Unity) Application::UpdateSceneIfNeeded
0x0000000140131B71 (Unity) Application::TickTimer
0x0000000141A8679D (Unity) MainMessageLoop
0x0000000141A88167 (Unity) WinMain
0x0000000141CEA11C (Unity) __tmainCRTStartup
0x00007FFC8BC113D2 (KERNEL32) BaseThreadInitThunk
0x00007FFC8BE254E4 (ntdll) RtlUserThreadStart

========== END OF STACKTRACE ===========