I, too, want to state that I just had the same problem.
I am running S1 3.5.0.
I updated a few weeks ago.
I recorded this track prior to 3.5.0 and have been running/mixing it fine since I updated to 3.5.0... until today.
Suddenly, the track disappeared from the Console, yet was in the arrangement view.
Had the same symptom of trying to unhide it in the Console area, but would only blink and hide again.
I, too, duplicated the track, and the duplicate is back in the Console -- I deleted the original one.
Very weird bug, it seems.