Query Folding not working when doing Inner Join in PowerQuery Editor

There is a bug in Power Query Editor that the inner join step does not fold. The subsequent steps after the inner join still fold, e.g. expanding the joined table. Only the Inner Join step does not fold. As a result, it took very long time to just display the "preview", which is supposed display only 199+ or 999+ rows. I believe this is a bug because Inner Join should be able to fold back to the server, as indicated in the subsequent steps after the inner join.