diff --git a/changelog.txt b/changelog.txt
index 157a981c..82a0d5e5 100644
--- a/changelog.txt
+++ b/changelog.txt
@@ -3,6 +3,7 @@ Version: 3.1.3
 Date: ???
   Changes:
     - Fix crash in beacon migration. Resolves https://github.com/pyanodon/pybugreports/issues/1515
+    - Fixed a crash when blueprinting inserters after another mod has edited the blueprint. Resolves https://github.com/pyanodon/pybugreports/issues/1526
 ---------------------------------------------------------------------------------------------------
 Version: 3.1.2
 Date: 2026-07-09
diff --git a/scripts/programmable-inserter.lua b/scripts/programmable-inserter.lua
index b36c7e3f..aefda625 100644
--- a/scripts/programmable-inserter.lua
+++ b/scripts/programmable-inserter.lua
@@ -497,17 +497,19 @@ py.on_event(defines.events.on_player_setup_blueprint, function (event)
     -- add tags and remove proxy inventories as necessary
     if prototypes.entity[entity.name].type == "inserter" then
       mapping = mapping or event.mapping.get()
-      local tags = entity.tags or {}
-      if mapping[index].type == "entity-ghost" then
-        tags["py-dynamic-inserter"] = (mapping[index].tags or {})["py-dynamic-inserter"]
-      elseif storage.programmable_inserters[mapping[index].unit_number] then
-        -- we only need to add data if data is in storage
-        tags["py-dynamic-inserter"] = {
-          drop_target_inventory = storage.programmable_inserters[mapping[index].unit_number].drop_target_inventory,
-          pickup_target_inventory = storage.programmable_inserters[mapping[index].unit_number].pickup_target_inventory
-        }
+      if mapping[index] then
+        local tags = entity.tags or {}
+        if mapping[index].type == "entity-ghost" then
+          tags["py-dynamic-inserter"] = (mapping[index].tags or {})["py-dynamic-inserter"]
+        elseif storage.programmable_inserters[mapping[index].unit_number] then
+          -- we only need to add data if data is in storage
+          tags["py-dynamic-inserter"] = {
+            drop_target_inventory = storage.programmable_inserters[mapping[index].unit_number].drop_target_inventory,
+            pickup_target_inventory = storage.programmable_inserters[mapping[index].unit_number].pickup_target_inventory
+          }
+        end
+        entity.tags = tags
       end
-      entity.tags = tags
     end
   end
   blueprint.set_blueprint_entities(entities)