In a mostly Vanilla Game (Harmony, Core + All DLCs, Hugslib, PCC, Mod Manager), I get an error when I try to access settings menu that selects which traits should not appear during a change. Any Idea why it does this?

[HugsLib][ERR] Exception during DoWindowContents: System.NullReferenceException: Object reference not set to an instance of an object
at PCC_Code.PCCSettings.get_disabledDefs () [0x00008] in <2feca6df9bea4deda809a8990f4604bd>:0
at PCC_Code.PCC_Mod.DoSettingsWindowContents (UnityEngine.Rect inRect) [0x00462] in <2feca6df9bea4deda809a8990f4604bd>:0
at HugsLib.Settings.Dialog_VanillaModSettings.DoWindowContents (UnityEngine.Rect inRect) [0x000e4] in <a56dbe2cf5184fe991f5fb736b3081b0>:0
UnityEngine.StackTraceUtility:ExtractStackTrace ()
Verse.Log:Error (string)
HugsLib.Utils.ModLogger:ReportException (System.Exception,string,bool,string)
HugsLib.Settings.Dialog_VanillaModSettings:DoWindowContents (UnityEngine.Rect)
Verse.Window:InnerWindowOnGUI (int)
UnityEngine.GUI:CallWindowDelegate (UnityEngine.GUI/WindowFunction,int,int,UnityEngine.GUISkin,int,single,single,UnityEngine.GUIStyle)