FULL PRODUCT VERSION :
java version "9.0.4"
Java(TM) SE Runtime Environment (build 9.0.4+11)
Java HotSpot(TM) 64-Bit Server VM (build 9.0.4+11, mixed mode)



ADDITIONAL OS VERSION INFORMATION :
Linux depsn116.inaf.cnrs-gif.fr 4.15.5-1-default #1 SMP PREEMPT Thu Feb 22 21:48:29 UTC 2018 (52ce732) x86_64 x86_64 x86_64 GNU/Linux


EXTRA RELEVANT SYSTEM CONFIGURATION :
OpenSuSE Tumbleweed
KDE desktop
Using Scala 2.12.4

A DESCRIPTION OF THE PROBLEM :
When using the setResizable function on the primary stage, the stage becomes unviewably small. The elements within are not visible, and neither are window decorations and close buttons. I've attached minimal reproducible code here: https://pastebin.com/dmhJqfrT

Here are some images of what's happening on my desktop with a JavaFX9 application I'm developing. 

setResizable(true): 

https://i.imgur.com/k41vU25.png

setResizable(false):

https://i.imgur.com/p8rIPHi.png


REGRESSION.  Last worked in version 8u162

ADDITIONAL REGRESSION INFORMATION: 
java version "1.8.0_162"
Java(TM) SE Runtime Environment (build 1.8.0_162-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.162-b12, mixed mode)


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
set the primary stage to unresizable.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The maximize button should disappear and the stage should not be resizable, but be the appropriate size for its content.

Something kind of like this:
https://i.imgur.com/k41vU25.png
ACTUAL -
The maximize and all other windowing buttons disappear, and while the stage is not resizable, it's also not big enough to display ANY of it's content

https://i.imgur.com/p8rIPHi.png

ERROR MESSAGES/STACK TRACES THAT OCCUR :
There are no error messages

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import javafx.application.{Application => JavaFXApplication}
import javafx.scene.Scene
import javafx.scene.layout.Pane
import javafx.scene.control.Button
import javafx.stage.Stage
 
class SetResizableExample extends JavaFXApplication {
  override def start(primaryStage: Stage): Unit = {
    primaryStage.setTitle("SuperCopyMan 2")
    val pane = new Pane()
    val button = new Button("click me")
 
    pane.getChildren.add(button)
 
    val scene = new Scene(pane, 500, 400)
    primaryStage.setScene(scene)
    primaryStage.setResizable(false)
    primaryStage.show()
 
  }
}
 
object SetResizableExample {
  def main(args: Array[String]): Unit = {
    JavaFXApplication.launch(classOf[SetResizableExample])
  }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
None. I have tried using stage.sizeToScene() and it has no effect whatsoever.