LIOS Scanner list update error:

I am running Ubuntu 20.04:
On: HP OfficeJet 4650.
With HPLIP 3.20.3 + dfsg0-2;
Using scanner w/ Xsane 0.999-8ubuntu2.1

In trying to run LIOS OCR program I get the following error:

"Scanner list update error: DriverSane object has no attribute 'max'."

Do I need to update HPLIP to the newest version? Xsane does work on other scans but not with LIOS.

Do I need to update HPLIP? If so, how do I update HPLIP 3.20.3?

Thanks for help in resolving this.

R