Notes editor doesn't auto-capitalize new sentences (iOS/iPad)

In the notes/body editor, new sentences don't automatically start with a capital letter - with both the on-screen and attached keyboard (reported on iPad). Autocorrect works, and other apps behave normally. Cause: the rich text editor's input field doesn't request sentence capitalization from the OS keyboard, so it defaults to none. The title field does set it, which is why only notes are affected.