Ghost image on minimized Tk window resizing

[MichaelDonahue]

Describe the bug
A minimized Tcl/Tk application that resizes its toplevel (main application) window corrupts the portion of the display where it was before it was minimized.

To Reproduce
romeo.txt

1. Run the attached Tcl/Tk script (I changed the usual .tcl extension to .txt so I could upload it): tclsh romeo.txt
2. When the "romeo" application window comes up re-position it so that it overlaps another application window, such as a terminal or text editor.
3. After a brief pause the romeo window will at 1 second intervals create and destroy a subframe, which causes the main romeo window to resize.
4. Minimize romeo
5. Observe the location where the romeo window had been. I see corruption in the screen display as illustrated in the screenshots below.

Expected behavior
The minimized window should not modify the screen display.

Screenshots



Screenshots of "Reproduce" steps 1, 3, and 5.

Client (please complete the following information):

• OS: Linux Ubuntu 22.04.4 LTS, also Rocky Linux 8.9, and Windows 10 22H2
• VNC client: TigerVNC
• VNC client version: 1.12.0 (Ubuntu), 1.13.1 (Rocky and Windows), also 1.8.0 on another Linux box.
• Client downloaded from: my Linux distribution(s), and https://tigervnc.org/ (Windows)

Server (please complete the following information):

• OS: Linux Ubuntu 22.04.4 LTS, also Rocky Linux 8.9
• VNC server: TigerVNC
• VNC server version: 1.12.0 (Ubuntu), 1.13.1 (Rocky)
• Server downloaded from: my Linux distribution
• Server was started using: systemd on Ubuntu, vncserver on Rocky Linux

Additional context
I do not see this bug when running TigerVNC vncserver 1.8.0 on an older CentOS Linux 7 machine, so it looks like the bug was introduced after 1.8.0 and on or before 1.12.0.

[CendioOssman]

Thanks for your bug report and test case. I can reproduce the issue here on RHEL 8.