The screen is connected to the macbook via hdmi, after waking up the external screen is black. How to fix?

Question

macOS

MacBook Pro Retina 15" MC975, runs on OS X El Capitan 10.11.2.
An external monitor is connected to it via hdmi, I work in the external monitor + laptop monitor mode.
When the laptop wakes up, the external monitor displays only black instead of the desktop screen The screen works, the cursor goes to it, but there is no desktop, no shortcuts, no windows on it, when you drag something onto it, it is dragged, but this is not visible, only the cursor is visible. monitor connection.

Answer 1

I had a similar problem when connecting via hdmi (the laptop froze for a few seconds when waking up from sleep). Googled it, they say that this is always the case, with Apple laptops and third-party monitors connected not via thunderbolt. I solved the problem with an hdmi to dvi adapter, which I had lying around from a vidyash since the days of the PC (cheap and cheerful).
Well, or buy an adapter from thunderbolt to the one you need.

Answer 2

I have a macbook with 2 type-c ports, it helps to poke the adapter from one port to another.