I took screenshot of just one version, it was problem with both on/off, at
least on my machine.

Just posting wm_size message after the change in your function solves
issues in both cases for me.

2017-01-11 9:39 GMT+01:00 martin rudalics <rudalics@gmx.at>:

> > There is a slightly cosmetic issue with above function. When one switches
> > back on decorations,
> > the frame will not resize properly and minibuffer will be not visible.
> It's
> > there but just
> > covered by frame. Just resizing emacs framefixes it.
> >
> > Adding call to PostMessage(hwnd, WM_SIZE,0,0) in Martins function fixes
> it.
>
> This is not necessary here.  And it would be strange since the idea is
> that the outer frame size remains unchanged.  Hence, any problem would
> manifest itself already when you remove the borders by leaving parts of
> the display area reserved for the frame not redrawn.
>
> The image you posted in the message you sent just now seems to confirm
> that.
>
> But I'm testing this on Windows XP and have not yet pulled the recent
> multi-thread Emacs changes.
>
> martin
>