With this summer's PulseAudio 9.0 release was support for Memfd-based transport. That support is now enabled by default in time for PulseAudio 10.

This feature is about using Memfd on modern versions of the Linux kernel as a transport / shared memory method in place of the existing POSIX SHM shared memory transport. Memfd has been around since Linux 3.17 and this transport method for PulseAudio should be more secure and modern -- for allowing better sandboxing/container support, etc.

The commit reads, "memfd support was introduced in 9.0, but disabled by default. No issues have been reported - now is a good time to enable it by default."

Look for this change in the upcoming PulseAudio 10.