VRCExpressions未設定でMA Menu Item系にパラメーター名を選択から設定しようとするとエラーが発生する

[c-colloid]

AvatarDiscriptorにExpressionParametersを設定していない状態（デフォルト状態を含む）でMA Menu Item(MA Menu Group/MA Menu Installerも)でパラメーター名をドロップダウンメニューから選択しようとすると選択ウィンドウが開かず以下のエラーが出ます

NullReferenceException: Object reference not set to an instance of an object
nadena.dev.modular_avatar.core.editor.ParameterGUI+ParameterTree+<FindParameters>d__11.MoveNext () (at ./Packages/nadena.dev.modular-avatar/Editor/Inspector/Menu/ParameterField.cs:280)
nadena.dev.modular_avatar.core.editor.ParameterGUI+ParameterTree.BuildRoot () (at ./Packages/nadena.dev.modular-avatar/Editor/Inspector/Menu/ParameterField.cs:237)
UnityEditor.IMGUI.Controls.TreeView+TreeViewControlDataSource.FetchData () (at <347e3e2bef8c4deb82c9790c6e198135>:0)
UnityEditor.IMGUI.Controls.TreeViewDataSource.ReloadData () (at <347e3e2bef8c4deb82c9790c6e198135>:0)
UnityEditor.IMGUI.Controls.TreeView+TreeViewControlDataSource.ReloadData () (at <347e3e2bef8c4deb82c9790c6e198135>:0)
UnityEditor.IMGUI.Controls.TreeViewController.ReloadData () (at <347e3e2bef8c4deb82c9790c6e198135>:0)
UnityEditor.IMGUI.Controls.TreeView.Reload () (at <347e3e2bef8c4deb82c9790c6e198135>:0)
nadena.dev.modular_avatar.core.editor.ParameterGUI+ParameterWindow.OnGUI (UnityEngine.Rect rect) (at ./Packages/nadena.dev.modular-avatar/Editor/Inspector/Menu/ParameterField.cs:140)
UnityEditor.PopupWindow.OnGUI () (at <347e3e2bef8c4deb82c9790c6e198135>:0)
UnityEditor.HostView.OldOnGUI () (at <347e3e2bef8c4deb82c9790c6e198135>:0)
UnityEngine.UIElements.IMGUIContainer.DoOnGUI (UnityEngine.Event evt, UnityEngine.Matrix4x4 parentTransform, UnityEngine.Rect clippingRect, System.Boolean isComputingLayout, UnityEngine.Rect layoutSize, System.Action onGUIHandler, System.Boolean canAffectFocus) (at <d30253adcd2a48faba9ee2264e211f5a>:0)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr, Boolean&)

TreeView has not been properly intialized yet. Ensure to call Reload() before using the tree view.
UnityEditor.IMGUI.Controls.TreeView:OnGUI (UnityEngine.Rect)
nadena.dev.modular_avatar.core.editor.ParameterGUI/ParameterWindow:OnGUI (UnityEngine.Rect) (at ./Packages/nadena.dev.modular-avatar/Editor/Inspector/Menu/ParameterField.cs:144)
UnityEngine.GUIUtility:ProcessEvent (int,intptr,bool&)

現在はダミーのExpressionParametersをAvatarDiscriptorに設定し、MAの設定が終わった後AvatarDiscriptorの設定をデフォルトに戻すことを回避策としています