Why will the Highlights I captured on my Windows system using GeForce NOW not play well or at all on my macOS system, or vice versa?

Highlights captured on one system are not compatible with the other due to incompatible standards.  As an alternative, VLC version 3.0 or later may be used on either system, but you may still encounter window size changes during playback due to resolution changes.  This can be prevented in the options for the application or playing the clip in fullscreen.