Order by project name is actually ordering by key

We recently upgraded our JIRA instance from 4.3.7. When performing the following query in the Issue Navigator:

status = Resolved ORDER BY project ASC

ordering is actually by key, though issues within a key are not in order.

For example, the above query results in:

I would expect to see all the "Clone" issues above all the "zZTOP" issues, ignoring the key completely:

This may be related to JRA-26897.