If you want to see a waveform for a track you can open it in an application called Sonic Visualiser. A web link is supplied in the action documentation.
This action will open a single selected file in the application. Note that you can disable the splash screen in the application's preferences. You may have to close the application or start a new session via File>New Session (⌘N) before launching a second file.
Actions: Launch Sonic Visualizer
2017-10-20 First release.