This is a tbar ceiling done the California (read seismic) way.
The blue highlighted wires are the ceiling grid support wires.
The yellow highlighted wires are the independent supports to the fixture. The fixture is screwed to the grid
main runner on the corners opposite those of the wires.
The duct and register are both supported by the sheet metal strap, and it is in turn supported, by an independent wire, to the structure. It is secured to the grid's main runner with screws
The tin stud seismic brace you see is screwed with multiple screws to the grid's main runner, and to the structure above. It must be perpendicular to the grid. (I think this occurs every 12 feet so that no spot on the ceiling is more than 8 feet from one).
The wires highlighted in red are seismic bracing. They are splayed in all 4 directions at angles, keeping the tin stud in compression (and securing the ceiling), and are also connected to the structure.
You can thank your lucky stars that you don't have to go through this.