TightVNC Browser rendering very slow

I have setup tunnel together via Zero Trust following this tutorial

https ://developers.cloudflare.com/cloudflare-one/tutorials/vnc-client-in-browser

My machine where vncserver is hosted is Ubuntu 22.04

extremly slow rendering begun after applying latest updates

not sure

xstartup config

Uncomment the following two lines for normal desktop:

unset SESSION_MANAGER

exec /etc/X11/xinit/xinitrc

xsetroot -solid grey
x-terminal-emulator -geometry 80x24+10+10 -ls -title “$VNCDESKTOP Desktop” &
#x-window-manager &

Fix to make GNOME work

export XKL_XMODMAP_DISABLE=1
/etc/X11/Xsession

gnome-session &
gnome-panel &
nautilus &
xsetroot -solid grey
vncconfig -iconic &
x-terminal-emulator -geometry 80x24+10+10 -ls -title “$VNCDESKTOP Desktop” &

export XDG_CURRENT_DESKTOP=“GNOME-Flashback:GNOME”
export XDG_MENU_PREFIX=“gnome-flashback-”