Safari only show site content when browser window is not focused (show white page instead of site content when Safari window is focused)

[BeshEater]

I've encountered strange behavior in the Safari browser. Essentially when the site is fully loaded it appears as a simple white page. It displays the site normally while it is still loading, but when it is finished I immediately get a white page instead. Also when I click outside of the browser window all content becomes visible again. + There are some Safari window sizes on which content also appears normally (but it doesn't work for all sites)

image: sickcodes/docker-osx:ventura
macOS Ventura version 13.6.3
Safari version 16.6

Video with this issue - https://youtu.be/6zl_dKLNOx4

White page instead of site content when Safari window is focused:

Normal page with all content when Safari window is not focused:

The issue is very similar to https://discussions.apple.com/thread/254759054 - and there it was fixed by setting VMware Fusion to use Retina Resolution. I don't know how to do something similar with KVM. I've tried to set different resolutions but it doesn't help.

Info output:

Linux besheater-ThinkPad-T440p 6.5.0-14-generic #14~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Mon Nov 20 18:15:30 UTC 2 x86_64 x86_64 x86_64 GNU/Linux
:0
1
PRETTY_NAME="Ubuntu 22.04.3 LTS"
NAME="Ubuntu"
VERSION_CODENAME=jammy
UBUNTU_CODENAME=jammy
Filesystem Size Used Avail Use% Mounted on
/dev/sda3 916G 172G 698G 20% /
QEMU emulator version 6.2.0 (Debian 1:6.2+dfsg-2ubuntu6.16)
Copyright (c) 2003-2021 Fabrice Bellard and the QEMU Project developers
libvirtd (libvirt) 8.0.0
total used free shared buff/cache available
Mem: 15Gi 5.7Gi 782Mi 475Mi 8.8Gi 8.8Gi
Swap: 2.0Gi 156Mi 1.8Gi
4
8
crw-rw----+ 1 root kvm 10, 232 Jan 16 18:01 /dev/kvm
total 8.0K
drwxrwxrwt 2 root root 4.0K Jan 16 03:29 .
drwxrwxrwt 20 root root 4.0K Jan 16 18:27 ..
srwxrwxrwx 1 root root 0 Jan 16 03:29 X0
root 1424 0.8 0.5 1816060 86000 ? Ssl 03:29 8:05 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock
root 32581 0.0 0.0 12300 2560 pts/4 S+ 19:19 0:00 grep --color=auto dockerd
e84b556c9bd7 sickcodes/docker-osx:naked "/bin/bash -c 'sudo …" About an hour ago Up About an hour 0.0.0.0:50922->10022/tcp, :::50922->10022/tcp wonderful_sanderson
kvm:x:109:
libvirt:x:138:besheater
libvirt-qemu:x:64055:libvirt-qemu
libvirt-dnsmasq:x:139:
docker:x:999:

[BeshEater]

When I posted this now I found it's the same issue as described here - #647

[sickcodes]

I never resolved this graphical issue in Ventura, but Safari works fine in Sonoma haha.