TrackingOptions.domainName lets Java and Kotlin callers select an active organization-owned custom hostname for link and open tracking, serialized as tracking_options.domain_name. A fluent TrackingOptions.Builder is available alongside the existing four-argument constructor, and requests that omit domainName keep their previous default tracking behavior.
Multi-value attendees and anyEmail filters on events, messages, threads, and drafts were sent as repeated query parameters (attendees=a&attendees=b). The API only keeps the last value in that form, so filtering on more than one value silently returned incomplete, order-dependent results. The SDK now comma-joins these values into a single parameter. This is backward compatible: attendees and anyEmail stay List types, and single-value calls are unaffected.