bug#28512: 26.0.60; undecorated frames on macOS 10.13 do not resize properly

[Alan Third]

On Sun, Sep 24, 2017 at 05:39:05PM -0700, Aaron Jensen wrote:
> 
> I may have something. If the initial frame is created with undecorated
> set from the beginning, it works. Likewise if you create a new frame
> after:
> 
> (add-to-list 'default-frame-alist '(undecorated . t))
> 
> So, the problem may have something to do with transitioning from a
> decorated frame to an undecorated frame. I remember seeing something
> in the iterm2 code about recreating windows in certain instances, but
> I don’t remember where I saw that.

I’m beginning to lean towards this being a bug in the 10.13
pre‐release, given the lack of evidence that this is intentional. Up
to 10.6 you couldn’t change a window’s styleMask, but they now provide
a function to do it, setStyleMask, and I don’t see any sign that
they’re getting rid of this capability.

I suppose the sensible thing to do would be to raise a bug report with
Apple and see if they say anything, or wait for the next release and
see if it’s still a problem.
-- 
Alan Third