Proposition 65 requires a business to give a "clear and reasonable warning" before knowingly exposing anyone in California to a listed chemical known to cause cancer or reproductive harm. For e-commerce selling physical goods into California, the warning (or a "WARNING"-labeled hyperlink) must appear on the product display page or otherwise be shown before the purchase is completed. Penalties run up to $2,500 per violation per day, with heavy private "bounty-hunter" enforcement.
Not currently part of a featured bundle — you can still run a check against this framework individually.
Upload your document and get a per-requirement gap analysis.