STR:
Open a new document and set the language to XML or HTML.
Paste the following two lines:

<NotepadPlus>
</NotepadPlus>

Delete the last >.

Result:
NPP crashes.

Notepad++ v8.3 (64-bit)
Build time : Feb 3 2022 - 03:39:05
Path : C:\Users---\Downloads\npp.8.3.portable.x64\notepad++.exe
Command Line :
Admin mode : ON
Local Conf mode : ON
Cloud Config : OFF
OS Name : Windows 10 Pro (64-bit)
OS Version : 2009
OS Build : 19042.985
Current ANSI codepage : 1255
Plugins : mimeTools.dll NppConverter.dll NppExport.dll