Framebuffer update rectangle too large

[Mojave Bob]

We are using the VNC Java Viewer to provide remote access to our support vendors through our SSL portal. It works really nicely. However, the remote user sometimes gets the error "Framebuffer Update Rectangle Too Large" when logging in to the VNC Authentication box.

Sometimes we can change the Cursor Shapes Updates to Ignore or Disable as a workaround, but I'd really like this to be a smooth process for my remote users. I see the problem existed at least as far back as 1.0.2, but apparently still exists in 1.0.8. I don't see any recent patches addressing this. Is there a real fix for this? What causes it?

Thanks for your help!