This is a followup of #13476: I use WinZip 21 (a bit older), which somehow pulls parts of the old style explorer context menu to is own context menu. With the following steps, the "Edit with Notepad++" item is duplicated:
I click the single "Edit with Notepad++" item in the WinZip contextmenu and a Windows prompt "choose an app to open this file type" appears (which did not happen before). And after this, there are two "Edit with Notepad++" items in the context menu: