This document contains draft text for changes under consideration for future extensions to the versatile supplemental enhancement information messages for coded video bitstreams (VSEI) standard (Rec. ITU-T H.274 | ISO/IEC 23002-7) to modify existing SEI messages, specify additional SEI messages, or specify other functionalities. This document also contains draft text for changes under consideration for future extensions to the VVC, HEVC, and AVC standards for specifying the use of SEI messages specified in VSEI in VVC, HEVC, and AVC bitstreams, respectively.