bug#53018: 29.0.50; pgtk child frame borders wont show

[Akira Kyle]

In GNU Emacs 29.0.50 (build 1, aarch64-unknown-linux-gnu, GTK+ Version 3.24.30, 
cairo version 1.16.0)
Repository revision: ab5ee3e29e916d4009b301841e9780aad564a6a0
Repository branch: master
System Description: NixOS 22.05 (Quokka)

Configured using:
 'configure
 --prefix=/nix/store/0fiqa453abl4c1c28g0baqs9s274s7ff-emacs-pgtkgcc-20220103.0
 --disable-build-details --with-modules --with-x-toolkit=gtk3
 --with-cairo --with-xwidgets --with-native-compilation --with-pgtk'

Window manager is sway and (pgtk-backend-display-class) is
"GdkWaylandDisplay"

Running the following lisp in emacs -Q:

(add-to-list 'load-path "~/path/to/posframe")
(require 'posframe)
(posframe-show " *my-posframe-buffer*"
                 :string "This is a test"
                 :position 1
                 :border-width 30
                 :border-color "red")


The child frame border look like appears for a split second before
disappearing and it isn't colored red but inherits the default
background color.