What is the difference between a display header and its more-options chevron?

Clicking a display’s header expands or collapses its entire block. The chevron beneath that block shows or hides additional menu items for the same display. Use the header to put a whole display aside, and the chevron to reveal less frequently used options while keeping its main adjustments visible.

The chevron belongs to the section above it. It appears only when that section has additional content to show, so it is different from clicking the next display’s name.

By default, opening another display’s more-options area closes the previous one. Changing which options are shown leaves each display’s connection state unchanged. See App Menu navigation and menu behavior settings for the available presentation choices.