The Chord Bar appears in Track View when the Chords track has the focus.  It allows you to make adjustments to the root name and inversion of the chord selected in the chord matrix.

These are the same controls that are available in the Edit Chord window.

Controls

Root Name

Selects whether to use a specific name for the root note of the chord.  This is only available where the root is an accidental note.  If not selected, the nominated default name is used.

Bass Pitch

Selects whether to use a specific bass pitch for the chord inversion.  If not selected, the bass pitch will be selected automatically based on the Chords track setup and the previous chord.

Inversion

Selects whether to use specific pitches for tones of the chord inversion.  If not selected, the inversion will be generated automatically based on the Chords track setup and the previous chord.  A specific inversion created in this way will be an ascending series starting from the bass pitch.

Custom Inversion

Opens the Custom Inversion window, which offers complete flexibility in selecting the tones of the chord inversion.  It does not even require the selection of a chord.