I don't know if this has been reported before but I noticed that Editorial doesn't appear to be detecting multiple languages/keyboards with iOS 10.
I tried with other apps (e.g. Apple Notes) and everything works as expected.
This is a new feature of iOS 10 not available in previous versions of iOS. Essentially, iOS checks what has been typed against all the dictionaries installed without the need to switch dictionary. This is useful if a phrase contains words from more than one language.