Noun
lightbar (plural lightbars)
English Wikipedia has an article on:lightbarWikipedia
A bar mounted on the roof of a vehicle, such as a police car, with rotating beacons or other lights to provide a visual warning.
A lightbar returns too, albeit either side of the touchpanel rather than on the top. Source: Internet
He was driving a black and white crown victoria, had added a colorless lightbar, restored the Whalen stuff inside so he had lights, sirens, bullhorn, added a bunch of ham radio equipment. Source: Internet
There's also some lighting effects on the DualSense controller, though they aren't nearly as prominent as the DualShock 4's lightbar. Source: Internet