This bug is a special bug of MariaDB with JDBC in LO Base:

Create two tables with the following code in MariaDB:
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CREATE TABLE `Person` (
  `ID` tinyint(3) NOT NULL,
  `Forename` varchar(100) DEFAULT NULL,
  `Surname` varchar(100) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;
CREATE TABLE `Zensuren` (
  `PersonID` tinyint(3) NOT NULL,
  `F1` tinyint(3) UNSIGNED DEFAULT NULL,
  `F2` tinyint(3) UNSIGNED DEFAULT NULL,
  `F3` tinyint(3) UNSIGNED DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;
ALTER TABLE `Person`
  ADD PRIMARY KEY (`ID`);
ALTER TABLE `Zensuren`
  ADD PRIMARY KEY (`PersonID`);
ALTER TABLE `Person`
  MODIFY `ID` tinyint(3) NOT NULL AUTO_INCREMENT;
ALTER TABLE `Zensuren`
  ADD CONSTRAINT `Zensuren_ibfk_1` FOREIGN KEY (`PersonID`) REFERENCES `Person` (`ID`) ON DELETE CASCADE ON UPDATE CASCADE;

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Insert some values in table "Person". Only one character for Forname will be enough.
Insert the same values for ID as created in "Person" into "PersonID".
Connect both tables in a query.
Only with JDBC-connection you will be able to add values to F1, F2 and F3. (Write protected with direct connection - don't know why).
Add '2' in first row of F1.
Move arrow down to next row.
'2' will be shown in next row.
Move down again.
'2' will move with the cursor.

Seems something is going wrong with refreshing when changing to next row.

All detected in LO 7.6.2.1, might be also in older versions. Seems to work well with AOO - so not a bug of JDBC-connection …