Sorry about that. I got sidetracked with the discussion about the truss + Vario rack.

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Edit: I know it won't answer the OP's question since it'll take the place of a Brompton bag in the front, but for information, Vincita (Thailand) makes a product that lets Brompton users hook up a Klickfix adapter to the brazed lug:


https://www.vincita.co.th/collection...pton-head-tube