External display for MacBook
I have Macbook Pro 16 and I'm connecting it to an external display via original Apple hub to HDMI. Sometimes after unblocking Mac external display shows black screen, but Mac detects it as connected and I can move mouse cursor over Mac screen. After reconnecting display It shows an image and loses it again approximately in 1 min. Also it shows image if I turn on display mirroring. I tested few HDMI cables. Also I used this monitor with my old Macbook Retina 2012 and all was perfect.
MacBook Pro 16", macOS 10.15