Jeroen Bakker continues his compositor improvement spree, now adding the ability to read Cryptomatte metadata from multilayer OpenEXR files. Previously, Cryptomatte metadata was only generated at render time.
This newest patch allows for workflows incorporating rendering on multiple different scenes, where compositors can now use Cryptomatte passes loaded from EXRs rendered outside the current scene. This also goes in the direction of planned changes to the Cryptomatte node, which will use metadata for name matching and color picking. Jeroen demonstrates the ability to read the metadata in the video below: