gtk-single-instance causes all window to close when attempting to close only one

[littleblack111]

this is a regression
if i have gtk-single-instance = true, spawn two windows, close any of them, the other will close too with

Gdk-Message: 13:41:45.434: Error 71 (Protocol error) dispatching to Wayland display.

Ghostty 1.1.0

Version
  - version: 1.1.0
  - channel: stable
Build Config
  - Zig version: 0.13.0
  - build mode : builtin.OptimizeMode.ReleaseFast
  - app runtime: apprt.Runtime.gtk
  - font engine: font.main.Backend.fontconfig_freetype
  - renderer   : renderer.OpenGL
  - libxev     : main.Backend.io_uring
  - desktop env: other
  - GTK version:
    build      : 4.16.12
    runtime    : 4.16.12
  - libadwaita : disabled
  - libX11     : enabled
  - libwayland : enabled

[littleblack111]

happens to other gtk apps too, prob gtk/nvidia(mentioned in other threads) issue