The after using search bar The UI glitches and this error is spammed

[NoTouchingKids]

When you search in any thing like storage or recipe item selector this error pops up and it is spammed until you close the workbench menu or something removing search filter also stops this error.

Exception filling window for ImprovedWorkbenches.Dialog_ThingFilter: System.NullReferenceException: Object reference not set to an instance of an object
  at Verse.Listing_TreeThingFilter.DoCategoryChildren (Verse.TreeNode_ThingCategory node, System.Int32 indentLevel, System.Int32 openMask, Verse.Map map, System.Boolean subtreeMatchedSearch) [0x000a9] in <b64badbf3c3d41018b3ca5d3e8c77771>:0 
  at Verse.Listing_TreeThingFilter.DoCategory (Verse.TreeNode_ThingCategory node, System.Int32 indentLevel, System.Int32 openMask, Verse.Map map, System.Boolean subtreeMatchedSearch) [0x000cf] in <b64badbf3c3d41018b3ca5d3e8c77771>:0 
  at Verse.Listing_TreeThingFilter.DoCategoryChildren (Verse.TreeNode_ThingCategory node, System.Int32 indentLevel, System.Int32 openMask, Verse.Map map, System.Boolean subtreeMatchedSearch) [0x00078] in <b64badbf3c3d41018b3ca5d3e8c77771>:0 
  at Verse.Listing_TreeThingFilter.DoCategory (Verse.TreeNode_ThingCategory node, System.Int32 indentLevel, System.Int32 openMask, Verse.Map map, System.Boolean subtreeMatchedSearch) [0x000cf] in <b64badbf3c3d41018b3ca5d3e8c77771>:0 
  at Verse.Listing_TreeThingFilter.DoCategoryChildren (Verse.TreeNode_ThingCategory node, System.Int32 indentLevel, System.Int32 openMask, Verse.Map map, System.Boolean subtreeMatchedSearch) [0x00078] in <b64badbf3c3d41018b3ca5d3e8c77771>:0 
  at Verse.Listing_TreeThingFilter.ListCategoryChildren (Verse.TreeNode_ThingCategory node, System.Int32 openMask, Verse.Map map, UnityEngine.Rect visibleRect) [0x0004a] in <b64badbf3c3d41018b3ca5d3e8c77771>:0 
  at Verse.ThingFilterUI.DoThingFilterConfigWindow (UnityEngine.Rect rect, Verse.ThingFilterUI+UIState state, Verse.ThingFilter filter, Verse.ThingFilter parentFilter, System.Int32 openMask, System.Collections.Generic.IEnumerable`1[T] forceHiddenDefs, System.Collections.Generic.IEnumerable`1[T] forceHiddenFilters, System.Boolean forceHideHitPointsConfig, System.Collections.Generic.List`1[T] suppressSmallVolumeTags, Verse.Map map) [0x0025b] in <b64badbf3c3d41018b3ca5d3e8c77771>:0 
  at ImprovedWorkbenches.Dialog_ThingFilter.DoWindowContents (UnityEngine.Rect inRect) [0x00053] in <c7af521044954100b3dda9f49f07ef03>:0 
  at (wrapper dynamic-method) Verse.Window.Verse.Window.InnerWindowOnGUI_Patch0(Verse.Window,int)
UnityEngine.StackTraceUtility:ExtractStackTrace ()
(wrapper dynamic-method) Verse.Log:Verse.Log.Error_Patch2 (string)
(wrapper dynamic-method) Verse.Window:Verse.Window.InnerWindowOnGUI_Patch0 (Verse.Window,int)
UnityEngine.GUI:CallWindowDelegate (UnityEngine.GUI/WindowFunction,int,int,UnityEngine.GUISkin,int,single,single,UnityEngine.GUIStyle)

Here is the log
https://gist.github.com/a5f95fd61d05922e4594248e9e811665