The claim is directly confirmed by the official announcement from Nikita Bier, X's head of product, on June 11, 2026, who introduced 'Big Charts' embeddable into posts via Cashtags and expandable by tapping, available on iOS and web, citing $TSLA. Multiple independent secondary sources (Watcher.Guru, Crypto Briefing, Kalshi Finance) corroborate the same announcement with the exact crypto/stock ticker examples (Bitcoin, Ethereum, TSLA). The feature builds on X's earlier 'Cashtags' rollout documented by The Block. All key claim elements—feature name, timeline display, expanded charts, and the Bitcoin/Ethereum/TSLA examples—are verified.