Takahe through 0.11.0 Cross-Site Scripting via javascript: URL Scheme

Takahe through 0.11.0 fails to restrict URL schemes in link hrefs within federated post content and profile summaries, allowing remote actors to inject javascript: links. Attackers can deliver federated content with malicious javascript: hrefs that execute in the instance origin when clicked, enabling session hijacking or impersonation of viewers.