The arguments (filters) for nested collections are based on the parent resource configuration, not on the collection's resource configuration.
PR is available now (#2970) - still needs regression tests to be merged, but is working correctly (just diff your generated schema if you're unsure) 馃檪
I thought that was the expected behaviour. I see the light at the end of the tunnel now!
Do you have an ETA for this to be merged in master? Can I help somehow to make things quicker?
Fixed in master and 2.4.
@luca-simonetti either wait for a release or use the dev version.