Twitter ($TWTR@US) and Square ($SQ@US) CEO Jack Dorsey has again trolled backers of Ethereum, the second-biggest cryptocurrency by popularity and market capitalization. Dorsey, a big supporter of apex cryptocurrency Bitcoin, posted a screenshot of how he created and synced a list of all Twitter accounts he follows, but the screenshot displays a tweet that suggests Ethereum is considered a scam. Dorsey is widely known to be a so-called “Bitcoin maximalist” and has refused to consider buying into Ethereum and other altcoins on several occasions. The Twitter CEO said on the company’s second-quarter earnings call in July that Bitcoin will be a “big part” of the company’s future. Twitter shares closed 0.3% lower in Wednesday’s trading, and Bitcoin is down 2.4% during the past 24 hours.