Black screen after desktop is shown 10.15.5

[shgew]

I have recently updated to 10.15.5.
While the update was installing, after every restart my monitor went black and displayed 'No signal' message. Every time that message appeared I simply reconnected the HDMI cable and the output was normal.
But after the update, every time my desktop appears after boot or my display sleeps, the monitor displays 'No signal' message and won't wake up until I reconnect the HDMI.
What could be causing this issue? Please, help.

 

[joaolfb]

Similar problem here. When computer wakes from sleep my monitor remains black. I need to switch hdmi input in order to wake the monitor.
No solution Yet.