openai/gpt-chat-latest → A (3:2)

Side A introduces a targeted security improvement by sanitizing untrusted Reddit `body_html` with `ammonia` before every `PreEscaped` render, adds a dedicated sanitization module, and includes tests that verify scripts and event handlers are stripped while benign markup is preserved. Side B fixes an important correctness issue by removing the shared browser delegate sentinel and updating session types and tests so multiple browser users can vote independently, but the XSS mitigation in A provides broader, long-term protection across all rendered Reddit content.