3.26.1 not converting Kepub format

I noticed that Calibre 3.26.1 not converting epub to the Kepub format when I transfer my epub ebooks to my Kobo Aura One.

The easy workaround is to rename the book extension to kepub.epub, but it use to do this automatically.

I confirm I still have the KoboTouchExtended 3.0.2 Plugin.