The whole-stack log stream sends service:null on every line, so the container filter dropdown only ever showed "All containers". docker compose logs already prefixes each line with the container name (and an RFC3339 timestamp via --timestamps); parse that prefix client-side to recover the container, populate the filter, and render time + container + message separately (cleaner than the raw prefixed line). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>