Does someone has context on this? It sounds better for users to be able to see the frames changing while scrubbing in order for them to see where they are scrubbing to. 

Should this be a WontFix?

I agree on the ideal use case that the user would be able to see the frames changing. However, on low end devices or slow networks, it takes a long time to update the viewport and the device becomes unresponsive and scrubbing becomes virtually unusable. I am not convinced the new scrubber controls will fundamentally change this fact, so I think a solution is necessary. 

I don't have a great sense of the magnitude of the problem, though, so we probably need to do some more work to figure out whether we should always do this or restrict it to specific device/network conditions.

Is this still wanted? Is it considered at in the new media controls? 

I will archive this. FWIW, I think we should do the opposite and show the new frames while scrubbing instead of waiting for the scrubber to stop moving.