Frame Debugger: Requires multithreaded rendering to be enabled

I've recently upgraded my project (Case 1108597) from Unity 2017.4 to 2018.4. Now I'm unable to use the Frame Debugger to profile a Windows 64bit player. It used to work in 2017.4.

When I try to connect, Unity outputs this error:
Failed to enable Frame Debugger on Remote Device: Requires multithreaded rendering to be enabled.

The build and UnityEditor run on the same PC, it's not a remote connection really. I didn't change any Player Settings too and I also can't find any multithreaded settings. The documentation mentions this too, but also does not provide information where to enable it.

The docs say:

• Enable development mode, checked
• Enable Run in background, checked
• Enable multithreaded rendering, ???

Here are my settings: