Hey @sk_monkeytyper, thanks for the detailed report. I confirmed that Cmd+Shift+N is still the default New Window binding in 3.15.6.
Could you try these checks?
Click inside a code editor tab, then press Cmd+Shift+N. Please let me know whether it fails there too, or only when focus is in chat, the terminal, or another panel.
Open the Command Palette and run Developer: Toggle Keyboard Shortcuts Troubleshooting.
Press Cmd+Shift+N once, then paste the new lines from the Keyboard Shortcuts Troubleshooting output here as text.
Run the same Toggle command again to stop logging.
Run Developer: Reload with Extensions Disabled and test the shortcut once more.
That output will show whether the shortcut reaches Cursor, which command it resolves to, and whether an extension or another binding is intercepting it.