Incomplete documentation for the `WITH` clause

https://mariadb.com/kb/en/with/

The `WITH` clause supports multiple CTEs in a single statement, e.g.:

WITH a AS (SELECT 1),
b AS (SELECT 2)
SELECT a.*, b.* FROM a, b

This (as far as I can see) is not documented anywhere.

In my opinion, it should be documented at a minimum by changing the documented syntax to reflect the functionality, and optionally by mentioning it explicitly.