Maximized stages do not resize when needed on Windows

[Martin Fox]

Christopher,

Did you enter a bug on this? I couldn’t find one. If you didn’t enter one I will.

It is a bug in JavaFX, we’re mishandling WM_WINDOWPOSCHANGING but the bug appears to be in some Java code that I’m not familiar with (notifyMoving in WinWindow.java).

Martin

> On Feb 16, 2026, at 1:51 PM, Christopher Schnick <crschnick at xpipe.io> wrote:
> 
> Other non-JavaFX applications work fine, they stay maximized and resize to the new size. So probably JavaFX does not like resizing a window when it is maximized.
> 
> On 16/02/2026 22:49, Thiago Milczarek Sayão wrote:
>> I think windows will let you resize a maximized window, which is weird.
>> 
>> The logical behaviour would be to unmaximize the window when moved.
>> 
>> Em seg., 16 de fev. de 2026 às 14:32, Christopher Schnick <crschnick at xpipe.io <mailto:crschnick at xpipe.io>> escreveu:
>>> On Windows, you can move a window (even if maximized) to another screen 
>>> with Win+Shift+Arrow key. When doing this, a JavaFX stage does not 
>>> resize itself to the new screen if the other screen has a different 
>>> size. You get stuck with an application where the titlebar looks like it 
>>> is in fullscreen, but it does not fill the screen.
>>> 
>>> I would suspect there is some kind of rule built into some JavaFX part 
>>> that internally prevents resizing maximized windows? Because I have only 
>>> seen this happen with JavaFX windows so far.
>>> 
>>> I can open a ticket for this, but I would have no idea how to fix this 
>>> issue.
>>> 

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