I finally watched (not sure why it took so long) Calum Waddell's 90 minute giallo documentary which is on the Arrow/Synapse Tenebre 4K UHD/blu-ray sets. I very much enjoyed it. What did surprise me was how Argento-centric it was, I think maybe almost 50% of it dealt with discussing Dario's work and career, including interviewing the man himself. Not a bad thing for his fans.
Would recommend checking it out if you haven't already done so, I'm pleased to have another Argento documentary in the collection.