Operating system: Windows-10-10.0.18362-SP0 64 Bits
Graphics card: GeForce RTX 2070 with Max-Q Design/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 457.30
Broken: version: 2.92.0 Alpha, branch: master, commit date: 2020-11-09 22:42, hash: rBb5d310b569e0
Short description of error
When "only show selected curve keyframes" is ON, the keyframes of all the unselected curves disapear, but if i box select an area where they are still there they interfere with normal selection
Exact steps for others to reproduce the error
Open a new scene.
Create a lot of keyframes in different channels in the default cube.
Bring in a Graph Editor.
Go to View > and turn on "only show selected curve keyframes"
Only select a channel or a couple of them in the graph editor
Draw a big rectangle over an area where there would be keyframes if there would be visible like in the video above.