Animation Clips aren't overlapping to create blend clips in Timeline

Apologies if I posted this to the wrong place or if I have missed something obvious. 

I am trying to blend some animation clips like it is described here:



https://docs.unity3d.com/Manual/TimelineBlendingClips.html



There is also an example of what I am trying to do here at 3:37



https://unity3d.com/learn/tutorials/topics/animation/using-timeline-working-animation-clips



When I drag my clips they don't overlap and create the blend clips it seems. Here is a video:



https://www.dropbox.com/s/8kprc5dpuphp331/blend-clips.mov?dl=0



I think I have read through the relevant docs and searched the forums and this doesn't seem to be common so maybe I am just missing something obvious?

 

I am embarrassed to say this seems to have resolved itself after a system restart.

Just sharing in case anyone else experiences something like it ¯\_(ツ)_/¯