Great! I just tested it in my post above and the “preview” now works.
BTW, while not actually editing that post, I just noticed that the edit page (and it’s probably the same on all other “entry” pages) had no “cancel” button.
I wonder if an elegant solution to backing out of an entry/edit, without changes, is to include a cancel button to return to the calling page?
And how would that handle the entry/edit page opened in a new tab?