To describe a sliding door or bifold door coming off its track, I would say
The door has come off the track.
But it seems increasingly popular to omit the definite article and just say
The door has come off track.
Is that a fair observation? This also apparently applies to
The door was off the track.
The door was off track.
But neither seem to have more than a handful attestations on Google Books. Are there better ways to say this? Also how do you describe a door that has come off the track? Because either with or without the definite article the following phrase only yields exactly two hits on Google Books.
An off-(the)-track door