~x-ai/grok-latest → A (3:2)

A repairs concrete mock-OAuth/Reddit failures (string split on "=" vs regex, getRequestBody vs getInputStream, null-safe token/state handling, response headers, handler try/catch) that had broken Playwright auth E2E, plus selector fixes in the login helper. B is a worthwhile UX consistency cleanup (SSR #new-thread-ui-slot and delete ExpandNewThreadForm/toolbar) but removes a working indirection rather than fixing correctness or restoring critical test capability.