Bug encountered when duplicating selection of tiles to another level

[CatWillSCRATCH]

I tried to duplicate a selection of tiles from one level to another by holding Ctrl+Alt and dragging to the other level; I then encountered the bug "Cannot read properties of undefined (reading '_hx_index') (TypeError)." The bug is reproducible.

I have two levels the same size next to each other; one is full of tiles and the other is empty.

I then select all of the tiles on the left level by dragging and holding down Shift+Alt.

Using Ctrl+Alt, I drag the selection to the level beside it.

Once I release and then click on the still empty level, it throws the same error.

I'm using Windows 10, and the LDtk executable file is on a USB drive.

Stack:

LDtk version: 1.5.3-64bits
Cannot read properties of undefined (reading '_hx_index')
TypeError
TypeError: Cannot read properties of undefined (reading '_hx_index')
    at tool_SelectionTool.useAt (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:262130:15)
    at tool_SelectionTool.stopUsing (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:25074:22)
    at tool_SelectionTool.stopUsing (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:261878:28)
    at page_Editor.onMouseUp (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:238385:23)
    at page_Editor.onHeapsEvent (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:238271:9)
    at h2d_Scene.dispatchListeners (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:142944:4)
    at hxd_SceneEvents.dispatchListeners (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:190121:6)
    at hxd_SceneEvents.emitEvent (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:189951:9)
    at hxd_SceneEvents.checkEvents (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:190037:10)
    at Boot.mainLoop (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:5148:16)

Processes:

#0 App
 |--- #364 page.Editor
       |--- #365 misc.FileWatcher
       |--- #366 display.WorldRender
       |--- #367 display.LevelRender
       |--- #368 display.Camera
       |--- #369 display.Rulers[--]
       |--- #370 tool.SelectionTool[Add] [RUNNING]
       |--- #371 tool.lt.DoNothing[--]
       |--- #372 WorldTool
       |--- #373 tool.PanView[--]
       |--- #871 tool.lt.TileTool[--]
 |--- #876 page.CrashReport

Log:

[EVENT]        LayerDefAdded
[RENDER]       Rendered level UI
[FILE]         Reading HTML template pivotEditor from cache
[RENDER]       Rendering world level data.Level#dfbe9fa0-d7b0-11ee-a55b-db203ee5026e "Level_0"...
[WARNING]      Full level render requested
[RENDER]       Rendering world bg...
[RENDER]       Rendering world level data.Level#0885a1a0-d7b0-11ee-a55b-edd3125e1e10 "Level_1"...
[RENDER]       Rendering world bg...
[EVENT]        LayerDefChanged 6
[FILE]         Reading HTML template pivotEditor from cache
[RENDER]       Rendering world bg...
[RENDER]       Rendering world level data.Level#dfbe9fa0-d7b0-11ee-a55b-db203ee5026e "Level_0"...
[RENDER]       Rendering world level data.Level#0885a1a0-d7b0-11ee-a55b-edd3125e1e10 "Level_1"...
[EVENT]        LayerDefChanged 6
[FILE]         Reading HTML template pivotEditor from cache
[RENDER]       Rendering world level data.Level#dfbe9fa0-d7b0-11ee-a55b-db203ee5026e "Level_0"...
[RENDER]       Rendering world bg...
[RENDER]       Rendering world level data.Level#0885a1a0-d7b0-11ee-a55b-edd3125e1e10 "Level_1"...
[RENDER]       Rendering world bg...
[RENDER]       Rendering world bg...
[RENDER]       Rendering world bg...
[USERACTION]   Closed panel #864 ui.modal.panel.EditLayerDefs
[RENDER]       Rendering world bg...
[EVENT]        LevelSelected 0
[USERACTION]   Opened level data.Level#dfbe9fa0-d7b0-11ee-a55b-db203ee5026e "Level_0"
[TIMELINE]     Garbage collected level: #3
[WARNING]      Full level render requested
[RENDER]       Rendering world level data.Level#dfbe9fa0-d7b0-11ee-a55b-db203ee5026e "Level_0"...
[RENDER]       Rendering world level fields data.Level#dfbe9fa0-d7b0-11ee-a55b-db203ee5026e "Level_0"...
[RENDER]       Rendering world level data.Level#0885a1a0-d7b0-11ee-a55b-edd3125e1e10 "Level_1"...
[USERACTION]   SelectionTool: Rectangle, mode=Add, in LayerInst#6 "MPM_Pink_Maze_Tiles" [Tiles]
[EVENT]        LayerInstanceChangedGlobally 6
[EVENT]        LayerInstanceChangedGlobally 2
[EVENT]        LayerInstanceEditedByTool
[USERACTION]   SelectionTool: mode=Add, in LayerInst#6 "MPM_Pink_Maze_Tiles" [Tiles]
[GENERAL]      Page started: page.CrashReport()
[FILE]         Loading page template: crashReport from C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/tpl/pages/crashReport.html
[ERROR]        Cannot read properties of undefined (reading '_hx_index') (TypeError)
[ERROR]        TypeError: Cannot read properties of undefined (reading '_hx_index')
    at tool_SelectionTool.useAt (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:262130:15)
    at tool_SelectionTool.stopUsing (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:25074:22)
    at tool_SelectionTool.stopUsing (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:261878:28)
    at page_Editor.onMouseUp (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:238385:23)
    at HTMLBodyElement.<anonymous> (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:232825:10)
    at HTMLBodyElement.dispatch (C:\Users\leasa\AppData\Local\Programs\ldtk\resources\app.asar\assets\js\jquery.min.js:2:43064)
    at v.handle (C:\Users\leasa\AppData\Local\Programs\ldtk\resources\app.asar\assets\js\jquery.min.js:2:41048)

[GENERAL]      
#0 App
 |--- #364 page.Editor
       |--- #365 misc.FileWatcher
       |--- #366 display.WorldRender
       |--- #367 display.LevelRender
       |--- #368 display.Camera
       |--- #369 display.Rulers[--]
       |--- #370 tool.SelectionTool[Add] [RUNNING]
       |--- #371 tool.lt.DoNothing[--]
       |--- #372 WorldTool
       |--- #373 tool.PanView[--]
       |--- #871 tool.lt.TileTool[--]
 |--- #876 page.CrashReport

[GENERAL]      Page started: page.CrashReport()
[FILE]         Loading page template: crashReport from C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/tpl/pages/crashReport.html
[ERROR]        Cannot read properties of undefined (reading '_hx_index') (TypeError)
[ERROR]        TypeError: Cannot read properties of undefined (reading '_hx_index')
    at tool_SelectionTool.useAt (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:262130:15)
    at tool_SelectionTool.stopUsing (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:25074:22)
    at tool_SelectionTool.stopUsing (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:261878:28)
    at page_Editor.onMouseUp (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:238385:23)
    at page_Editor.onHeapsEvent (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:238271:9)
    at h2d_Scene.dispatchListeners (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:142944:4)
    at hxd_SceneEvents.dispatchListeners (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:190121:6)
    at hxd_SceneEvents.emitEvent (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:189951:9)
    at hxd_SceneEvents.checkEvents (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:190037:10)
    at Boot.mainLoop (file:///C:/Users/leasa/AppData/Local/Programs/ldtk/resources/app.asar/assets/js/renderer.js:5148:16)

[GENERAL]      
#0 App
 |--- #364 page.Editor
       |--- #365 misc.FileWatcher
       |--- #366 display.WorldRender
       |--- #367 display.LevelRender
       |--- #368 display.Camera
       |--- #369 display.Rulers[--]
       |--- #370 tool.SelectionTool[Add] [RUNNING]
       |--- #371 tool.lt.DoNothing[--]
       |--- #372 WorldTool
       |--- #373 tool.PanView[--]
       |--- #871 tool.lt.TileTool[--]
 |--- #876 page.CrashReport
 |--- #877 page.CrashReport

[FILE]         Cleared all file watches