Green’s Dictionary of Slang

bubbler n.1

[bubble v.1 ]

a swindler.

[UK] in J. Malcolm Anecdotes of Manners and Customs (1808) 70: The hurry of our Stock-jobbing bubblers, especially, has been so great this week [...] there has been nothing but running about from one Coffee-house to another.
‘Whipping-Tom’ In Praise of Knavery III Preface: I wish I could say all Bublers, Projectors and Scheme Makers were not Knaves.
Conquerors 9: Bubblers and bubbled meanly / Take their stand.
T. Fischer Observer 6 Jan. 🌐 [Bitcoin’s] retinue has accommodated an incredible rogues’ gallery. There have been old-fashioned cony-catchers, saltimbancos and bubblers who did a runner with other people’s money in the time-honoured manner.