Editor crash when creating Window node

[KoBeWi]

Godot version:
5f1107a

OS/device including version:
Windows 10

Issue description:
When you add a node of type Window, the editor will crash without backtrace.

[bruvzg]

Can't reproduce on macOS, adding Window node opens new window (deleting node closes it), and all of its children are displayed in this Window and are not interactive, that's probably is not a right way to handle it.

[ThakeeNathees]

for me (windows10) it just creates 33 windows nodes at the top left corner of the screen and then the editor become extremely slow.
I guess when a new window get focus it tries to handle the event which handled earlier by the last window,

[bruvzg]

I guess when a new window get focus it tries to handle the event which handled earlier by the last window

I fixed similar behaviour on macOS in #37339 (event handler called for a second time from the windowDidBecomeKey event, causing multiple error prints when popup is opened), Window might have the same issue.