Tried to fetch an item which has a rich text field containing a twitter embed through Integromat, but the entire embed code is simply gone from the resulting string (instead an empty<div></div> is left behind).
Then tried exporting the collection items using Webflows “export” button in the cms and found the same thing: All embeds are removed from the rich text fields.
I don’t think this is intended (why would removing parts of an export be intended, after all) and is a bug on Webflow’s end.