@holroy Thanks but those don’t address this specific issue, which is about creating a new note from a side-by-side view, having that new note replace the current one (not opening a new tab) without touching the mouse.
Using the Quick Switcher does work, but muscle memory and convenience has me reaching for ⌘N most of the time. Up until the 1.x releases, it always worked that way so I’d prefer if there was at least an option to have it behave as it did before. If I want to open a new tab, there’s a specific command for that (⌘T).
I created a small plugin to help with this situation. It doesn’t try to automatically do anything, but provides a couple of functions and a toolbar button to automatically arrange the view in a side-by-side split mode (edit/preview) in either horizontal or vertical layout, and optionally (on by default) close any other unrelated panes.
Another hotkey can be configured to specifically call the “close all other panes except the active one” function for convenience.
I submitted it for review, so it will hopefully be available for download shortly. For now if anyone wants to test, just download the release and pop it into your Obsidian plugins dir…