Re: src/nsterm.m: fix window tabbing on macOS

[Paul W. Rankin]

> On 28 May 2021, at 7:51 pm, martin rudalics <rudalics@gmx.at> wrote:
> 
> >> Why?  Have you `tab-bar-mode' turned on or have you set the
> >> `tab-bar-lines' frame parameter?
> >
> > It's important to note that this is not related to `tab-bar-mode'. These 
> > tabs are part of the OS's native window manager chrome.
> 
> I see.  So what does really "grow" and not "shrink": The window manager
> frame or the Emacs frame?  If it's the former, then the behavior should
> be seen by displaying any other application's windows in the window
> manager frame and the behavior is not Emacs specific.  Right?
> 
> martin

This might be best illustrated with a quick video showing how the Emacs.app 
frame behaves when creating a new tab vs a native macOS app:
https://f002.backblazeb2.com/file/pwr-share/emacs_nsterm.mov (16MB)