In neither browser.
When I press Ctrl+N I get a new browser window.
Ctrl-W closes the tab
Ctrl+Sift+P applies that shortcut to the browser's action, not the remove machine.
Mind you I am on opensuse Tumbleweed, X. Same issue with Fedora 42 Wayland.
Browsers are either Chrome or Firefox.
(What is fixed is the scroll width, but this is for another thread)