Status of CRYOSPARC_TIFF_IO_SHM in > v4.5.3?

What is the status of this variable in 4.7 and 5.0?

Environment Variables (v5.0+) | CryoSPARC Guide says: (available in CryoSPARC versions 3.2 through 4.5.3) When reading TIFF or EER movie files, CryoSPARC reads the entire file into memory before decompressing. This significantly improves performance on some networked file systems but uses more memory. Set to false to perform decompression directly from disk

Which sounds like the variable only exists until 4.5.3? Is the default changed now or does it just not exist?

This week we found an instance where we upgraded to Cryosparc 5 and saw huge improvements when setting:
CRYOSPARC_TIFF_IO_SHM=true

Looking for a definitive answer as to status. Thanks!

Starting with version 4.6, CryoSPARC reads the entire file into memory, CRYOSPARC_TIFF_IO_SHM should no longer have any effect.