A dark-themed webpage titled “Authenticate on Mastodon.” At the top, in orange text, it says “Development mode active.” Below that, a large gray box displays “Your authentication PIN:” followed by a bold, centered four-digit PIN “7626.” A small line of text underneath reads “Expires in: 9m 42s.” Beneath the PIN, there is an orange dashed box labeled “DEBUG MODE: Share message:” showing the text “FediAuth login PIN: 7626 for Fluffy’s flohmarkt on example.org.” Under that, there is a gray expandable button labeled “(Debug) All Platform Share URLs (16 platforms).” Next, a line with an orange rocket emoji and link text “Open Pre-filled DM (mastodon)” appears, followed by a small instruction: “Make sure only the recipient can see this message.” Below it, there is a circular loading animation with the text “Waiting for your message...” The bottom section, in a gray box, is titled “How to complete authentication:” in bold white text. It lists four steps: Click the button above to open a pre-filled compose window. Set visibility so only @auth@example.org