Welcome to our forums @JamesCRocks 
You’re right, that’s a known bug in LXPanel on Ubuntu 24.04. The missing section of the taskbar usually happens because the “Desktop Pager” applet is crashing or resizing incorrectly.
You can access Panel Preferences by right-clicking on an empty area of the taskbar (not an icon). If you don’t see the option, it’s likely that your panel is locked or overlapping the screen edge. Try this from a terminal:
lxpanelctl config
That should open the same configuration window. If it doesn’t, you can also edit the config directly:
nano ~/.config/lxpanel/LXDE/panels/panel
Then look for the line:
Plugin {
type=desktop pager
}
and delete or comment it out. Save and restart the panel:
lxpanelctl restart
That usually fixes the cutoff issue.
If you’re still missing part of the panel afterward, check your display scaling in Monitor Settings LXDE sometimes inherits fractional scaling values from newer Ubuntu builds. Setting it to 100% and logging out/in may help too.