Thank you for sharing this - I think apple does this just to sell new monitors -and I paid way to much for my LED cinema - and it is still working beautifully - Hopefully this works!If I'm reading things correctly, you need a TB3 (using a USB-C connector) to MiniDP adapter. I used the same thing for my '18 Mini, scored them off of Amazon.
I used a pair of these from Cable Creation, $9.99:
CableCreation USB C to Mini DisplayPort 4K@60Hz, Type C to Mini DP Adapter (Not Thunderbolt Adapter),Compatible with MacBook Pro 2017,Chromebook Pixel,Surface Book 2,XPS 13,Yoga 920,Aluminum Black
CableCreation USB C to Mini DisplayPort 4K@60Hz, Type C to Mini DP Adapter (Not Thunderbolt Adapter),Compatible with MacBook Pro 2017,Chromebook Pixel,Surface Book 2,XPS 13,Yoga 920,Aluminum Blackwww.amazon.com
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