The APERTURE table in a 2D longslit image is not readable with IRAF `tread`

[KathleenLabrie]

In IRAF, fxhead shows the APERTURE table as a standard BINTABLE, just like the PROVENANCE table. However, while I can tread the PROVENANCE table, I cannot tread the APERTURE table. tread does not see it at all. I get the "does not exist, do you want to create it" message.

This might indicates that there is something that does not respect the FITS standard in that table.

When loaded with astrodata, the table opens fine as an astropy Table.