@martin-olsson This is a possible candidate for using a third-party “macro” program to create specific behaviour on your computer. I use a downloaded tool called “AutoHotkey” but I haven’t created with it recently.
As far as I remember, things that an AutoHotkey macro can do include:
Read the title bar of a program
Bring a program (Notepad++) to foreground and out of being minimized
Send a keystroke to a program (Ctrl N new document)
So you could have an icon on your screen that does all of that from one click.
Other options are possible, such as always waiting for YOU to foreground Notepad++ and THEN send Ctrl N each time, or, to see if the title bar says “new” for a newly created document already.
Or it could just make your middle mouse button send Ctrl N.