Thanks to Grok for the help figuring this one out and creating the code. So apparently there's an issue with WeaponPart items in conjunction with and setMountOn during initialization when you open the item generation menu. What Grok came up with was a way to skip the code if it is a WeaponPart. I'm thinking that modders are using this old code for their b42 mods but its no longer in the game. the only downside to this is you can no longer spawn in weapon parts but imo its better than not being able to spawn anything in.

For this fix you need to go to this file: Steam\steamapps\workshop\content\108600\3386556284\mods\DebugMenu\42.0\media\lua\client\IS\ISItemGenerateUI.lua.

Then you'll need to replace the entire "iniList" function with the below code. It should be between lines 33 and 77. Don't remove lines 30 and 31, that's part of the code above it which is ok.

function QNW_DMItemGenerateUI:initList()
local allItems = {}
local modMap = {}
local mods = {}

local items = getScriptManager():getAllItems()
for i = 0, items:size() - 1 do
local itemScript = items:get(i)
local ItemType = itemScript:getFullName()
if ItemType and ScriptManager.instance:getItem(itemScript:getFullName()) then
-- Check item category before instantiating
local itemCategory = itemScript:getTypeString() -- e.g., "WeaponPart", "Food", etc.
if itemCategory ~= "WeaponPart" then -- Skip WeaponParts to avoid crash
local item = instanceItem(itemScript:getFullName())
if item and not itemScript:getObsolete() and not itemScript:isHidden() then
local modName = item:getModName()
if not modMap[modName] then
modMap[modName] = {}
table.insert(mods, modName)
end
table.insert(modMap[modName], item)
table.insert(allItems, item)
end
end
end
end
table.sort(mods, function(a, b)
return not string.sort(a, b)
end)

local cat = QNW_DMItemGenerateTable:new(0, 0, self.panel.width, self.panel.height - self.panel.tabHeight, self)
cat:initialise()
self.panel:addView(getText("IGUI_QNW_DebugMenu_All"), cat)
cat:initList(allItems)
cat = QNW_DMItemGenerateTable:new(0, 0, self.panel.width, self.panel.height - self.panel.tabHeight, self)
cat:initialise()
self.panel:addView("Project Zomboid", cat)
cat:initList(modMap["Project Zomboid"])

for k, v in pairs(mods) do
if v ~= "Project Zomboid" then
cat = QNW_DMItemGenerateTable:new(0, 0, self.panel.width, self.panel.height - self.panel.tabHeight, self)
cat:initialise()
self.panel:addView(v, cat)
cat:initList(modMap[v])
end
end
self.panel:activateView("Project Zomboid")
end