From 981fef3160672079ec2b96bfda602ccea69dfd42 Mon Sep 17 00:00:00 2001
From: Myk Taylor <myk002@yahoo.com>
Date: Mon, 20 Nov 2023 16:13:47 -0800
Subject: [PATCH] only clean up actual data records

---
 plugins/lua/sort/sortoverlay.lua | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/plugins/lua/sort/sortoverlay.lua b/plugins/lua/sort/sortoverlay.lua
index ce50ac98a..fb06a5f04 100644
--- a/plugins/lua/sort/sortoverlay.lua
+++ b/plugins/lua/sort/sortoverlay.lua
@@ -61,7 +61,9 @@ function SortOverlay:overlay_onupdate()
         not dfhack.gui.matchFocusString(self.viewscreens, dfhack.gui.getDFViewscreen(true))
     then
         for key,data in pairs(self.state) do
-            do_cleanup(self.handlers, key, data)
+            if type(data) == 'table' then
+                do_cleanup(self.handlers, key, data)
+            end
         end
         self:reset()
         self.overlay_onupdate_max_freq_seconds = 300