Windows splitting is actually quite sophisticated you can split horizontally or vertically and split successive sections of the screen. You can balance windows in one dimension or by area. You can do this automatically as you create or destroy windows if you like.

You can have new splits inherit the file you are already editing or show a blank buffer. Further closing a split doesn't kill the buffer or make you decide at that point whether to save a buffer it just destroys the view not the thing.

Native tabs interact with splits in one of two ways. Either as an array of window arrangements at top of window or an array of buffers within a particular split.

You can manually resize a split with the mouse and in fact you can create them via the file menu which also shows the key binding to activate the functionality beside the option ensuring that the 2nd through 10 millionth time you need the functionality you can just press a few buttons.

It's not opening external apps like clicking a link in your email and having your regular web browser open the url its creating a pyqt app within the space of your emacs/tab/split that you can interact with via elisp

https://github.com/manateelazycat/emacs-application-framewor...