Margaret turns and runs up the aisle twice after the wedding.
After Balthazar's song, Benedick leaves his deckchair without folding it properly. In a subsequent shot the chair is folded perfectly.
During Balthazar's song, Benedick is hiding behind the hedge, but when the camera shot changes, he is by the fountain, in clear view of Signor Leonato, Claudio, and Don Pedro.
Except for those in the foreground in one run of shots, the lanterns at the masked ball are lit by electric light bulbs.
The masquerade ball features an accordion, which was not invented until 1822.
A deckchair is present. This was first patented in the late 19th century.
As the wedding party emerges from the front door in the final shot, the crane used to achieve the elevated view is briefly visible.
When the ladies of the household are hurriedly bathing (the opening credits are still running), one lady's bottom has a distinctly modern bikini tan.
After the wedding fiasco, Beatrice prays to a plain cross instead of a crucifix with the Christ figure on it - in Catholic Sicily.