This dates to early 1880s I think but the information in here is relevant to our discussion on this thread ref French and American similarities.
See page 400 for information on how someone from Boston allegedly bought glass samples of each item from Compagnie des Cristallerie de Baccarat and then, the report says, those samples were copied and the French sales to the States ceased thereafter:
https://www.google.co.uk/books/edition/Commercial_Relations_of_the_United_State/gIs8AQAAIAAJ?hl=en&gbpv=1&dq=davenport+glass&pg=PA415&printsec=frontcoverAs I say, this dates to I think the early 1880s though and is referencing copying allegedly happening 4 or 5 years earlier so 1870s ish: see photo.
Unfortunately the report merely talks about Baccarat launching new coloured glass designs and that samples of each of those were bought. It doesn't describe exactly what the designs were, what the colours were, or whether they were opaline glass. So not much help to us.