Keyboard shortcut to switch windows?

Does anyone know what the keyboard combo is to switch windows and move focus to that Window? (Similar to Alt+Tab in modern operating systems) In OpenStep 4.2 at least, Command+Up/Down Arrow does switch which window is on top, but it does not change focus to that window. Focus/keyboard entry remains in the original window.

Here are a bunch o cool things you can do on a NeXT towards end of doc https://www.blackholeinc.com/docs/NeXT%20Service%20Manual%202%20Sections%204%205%206%20good%20Newby%20Stuff!_OCR.pdf

Thanks for providing this document, it has some interesting stuff in it.. Unfortunately it didn't answer my question... Maybe it only proves that it's not possible? It talks about changing the 'key' window but only mentions that you must click a window to make it the focused/key window. The document provides keyboard shortcuts for other operations but not this.

Hi @nullvalue, I worked many years with NeXTstep and OpenStep, but can not remember any such feature unfortunately. But of course this does not mean that it does not exist.

I wonder if this functionality could be implemented by modifying the WindowServer's windowPackage.ps postscript code.
 
The NeXT FAQ at  https://www.levenez.com/NeXTSTEP/faq.html (https://www.levenez.com/NeXTSTEP/faq.html) (section 4.35) mentions a modification to that file that enables an Alt-right click shortcut to kill an application window (source code at https://ftp.nice.ch/peanuts/GeneralData/Documents/faq/_NeXTFAQ.d/NeXT-FAQ/examples/windowpackage.patch (https://ftp.nice.ch/peanuts/GeneralData/Documents/faq/_NeXTFAQ.d/NeXT-FAQ/examples/windowpackage.patch)).

However, the file contains almost 2000 lines of postscript code without any comments...