I don’t know if this is a bug or a feature request but…
Z-Index doesn’t work on TeleportToPrivateServer ScreenGui’s. Repro: Make a ScreenGui and put a Frame with Z-Index 10 in it. Now for the place being teleported to create a ScreenGui and put a Frame with a Z-Index 1 in it.
The Z-Index 1 Player ScreenGui will appear above the Z-Index 10 TeleportScreenGui Frame. TeleportToScreenGui should have either it’s Z-Index fixed, or rendered above ScreenGui’s in the PlayerGui.