Invalid Authentication Plugin (no replies)

Hi, I have problem with Workbench.

When using "Server -> User and Privileges" I get the following message for each user:
"Invalid Authentication Plugin: user xxxx@% has plugin type mysql_native_password, which is not listed as a known authentication plugin by the server."

Also the list of databases in tab "Schema Privileges" is empty, therefore I cannot assign user privileges.

This prevents me to change/edit users and makes Workbench useless.

I searched for the solution on forums and on Google, but found only some 7 years old posts (Workbench 5.x) with no solution.

I am running Workbench 8.0.17, Mysql-community-server 8.0.17 on Fedora 30.

Help would be much appreciated since I am totally stuck with this.

Gorazd