## Trial

Renders one pandas design-options section in a Chopin document with a gallery, comparison table, expandable detail, and a private reader filter. Two seven-line OpenUI sources rearrange the same option records; an ordinary document provides the comparison. The source is [pandas issue 54154](https://github.com/pandas-dev/pandas/issues/54154) at frozen checkpoint `c1`. The screenshot is source evidence; the three small spreadsheet specimens are labeled illustrations.

## Visual preview



## Verification

- 17 focused unit and dialect tests; 3 Playwright tests against isolated PostgreSQL. - Type checks, repository CI, production build, and wide/narrow preview checks pass. - Initial JavaScript remains 249,951 B raw. Total emitted JavaScript grows 49,533 B gzip against `f1e81673`; the OpenUI lazy chunk itself is 47,165 B gzip.

## Recommendation

Adapt this for bounded document components and keep OpenUI experimental. Its native package entry is private, and the Copilot CLI captured invalid source after one attempt and one repair. The evidence does not establish whether the model or CLI formatting inserted the line breaks. The manual examples are the rendered trial. The [trial report](experiments/openui-composition-trial/README.md) preserves source, model output, and measurements.