In this Canvas release (August 17), the Conferences interface (BigBlueButton) supports breakout rooms and closed captioning. Additionally, Conferences is WCAG 2.0 AA Accessible, with some exceptions. In Discussions, the option for students to add file attachments is enabled by default.
As part of the new update schedule, Production Releases no longer have bug fixes; those are pushed out in smaller releases over the month.
View the Canvas Release Notes (2019-08-17).