Validating "summary ~ echo("*JIRA", "CONFLUENCE")" does not work.

The query "summary ~ echo("*JIRA", "CONFLUENCE")" does not return an error message during validation, while the query "summary ~ echo("*JIRA")" does.

The echo function simply echos its arguments back as query literals. It does not return a list but may return multiple query literal objects (which is allowed and expected under JQL).