Add NewTempWindow to the new test window file

test/window.go

@@ -1,6 +1,8 @@
 package test
 
 import (
+	"testing"
+
 	"fyne.io/fyne/v2"
 )
 
@@ -18,6 +20,16 @@ type window struct {
 	menu      *fyne.MainMenu
 }
 
+// NewTempWindow creates and registers a new window for test purposes.
+// This window will get removed automatically once the running test ends.
+//
+// Since: 2.5
+func NewTempWindow(t testing.TB, content fyne.CanvasObject) fyne.Window {
+	window := NewWindow(content)
+	t.Cleanup(window.Close)
+	return window
+}
+
 // NewWindow creates and registers a new window for test purposes
 func NewWindow(content fyne.CanvasObject) fyne.Window {
 	window := fyne.CurrentApp().NewWindow("")