AUTO_INCREMENT column gets unexpected value after INSERT -2

After inserting negative -2 in an auto-incremented column, the new generated serial jumps from 1 to 3, when it should be 2, according to the documentation:

https://mariadb.com/kb/en/auto_increment/#setting-explicit-values

The doc shows examples with positive values, but there is a clear sentence:

If the new value is lower than the current maximum value, the AUTO_INCREMENT value remains unchanged.

Which should include negative explicit values ...