Controls.ButtonClicked event never be called when program has loop

[nonkit]

Controls.ButtoClicked event never be called when the program has a loop.
Sample code is:

' doesn't work with SBO 1.0
Not["True"] = "False"
Not["False"] = "True"
show = "True"
rect = Shapes.AddRectangle(100, 100)
Shapes.Move(rect, 100, 100)
GraphicsWindow.BrushColor = "Black"
Controls.AddButton("Toggle", 10, 10)
Controls.ButtonClicked = OnButtonClicked
While "True"
  If buttonClicked Then
    show = Not[show]
    If show Then
      Shapes.ShowShape(rect)
    Else
      Shapes.HideShape(rect)
    EndIf
    buttonClicked = "False"
  Else
    Program.Delay(500)
  EndIf
EndWhile

Sub OnButtonClicked
  buttonClicked = "True"
EndSub

Following debug screen shows the event handler is under the program in its call stack.

But following code (doesn't have a main loop) runs properly:

' works with SBO 1.0
Not["True"] = "False"
Not["False"] = "True"
show = "True"
rect = Shapes.AddRectangle(100, 100)
Shapes.Move(rect, 100, 100)
GraphicsWindow.BrushColor = "Black"
Controls.AddButton("Toggle", 10, 10)
Controls.ButtonClicked = OnButtonClicked

Sub OnButtonClicked
  show = Not[show]
  If show Then
    Shapes.ShowShape(rect)
  Else
    Shapes.HideShape(rect)
  EndIf
  buttonClicked = "False"
EndSub

In the case above, there are no Program in the call stack.

Following code is just a subroutine sample:

OnButtonClicked()

Sub OnButtonClicked
  buttonClicked = "True"
EndSub

This is just normal subroutine appearing on the main Program in the call stack.

[Caseysch]

Minimum repro:

Controls.AddButton("Click", 10, 10)
Controls.ButtonClicked = OnButtonClicked

Sub OnButtonClicked
  TextWindow.WriteLine("subroutine called")
EndSub

' This loop prevents the subroutine from being called
While "True"
  Program.Delay(500)
EndWhile

[Caseysch]

Bumped up to pri/1: affects tutorial and probably most games