To meet accessibility requirements, all uses of auro-dropdown must have a valid label. See the following options:

1. Use the label content slot
2. Use aria-label to insert label content that will only be read by screen readers
3. Use aria-labelledby to reference a label from another element on the page

Not including one of the above options will result in your UI being non-compliant with Alaska's accessibility policies.

The dropdown can be opened with the following actions:

1. Clicking/tapping on the trigger.
2. Tabbing to the trigger and using the Enter or Space keys.
3. Programmatically via another control in the UI calling the show() method.

The dropdown can be closed with the following actions:

1. Clicking anywhere in the view outside of the dropdown.
2. Using the Escape key.
3. Programmatically via another control in the UI calling the hide() method.

When the desktopModal attribute is set, the dropdown behaves as a modal dialog on desktop viewports:

• All sibling elements on the page are marked inert, preventing interaction with content outside the dropdown.
• Focus is trapped within the bib content using a Tab-key handler.
• The inert state and focus trap are automatically cleaned up when the bib is closed or the component is disconnected.

In fullscreen mode, the native <dialog> showModal() API provides equivalent behavior, so desktopModal only applies to desktop-sized viewports.

The trigger is a focusable element and participates in the standard tab order, responding to Tab and Shift+Tab key events per native browser behavior, i.e., these keys step through the browser tabindex sequence.

When the component is disabled it is removed from the tabindex sequence. VoiceOver's virtual cursor (swipe navigation) can still encounter the component, but standard keyboard Tab navigation skips it.

When the bib is collapsed, the bib content is excluded from the tab sequence. When expanded, focusable elements within the bib content are included in the natural tab order. In fullscreen mode, focus is trapped within the bib, and the tab sequence cycles through the bib content focusable elements until the bib is closed or the viewport no longer meets the fullscreen condition and is rendered as a popover.

When the desktopModal attribute is set, focus is also trapped within the bib on desktop viewports. All sibling elements on the page are marked inert, preventing interaction with content outside the dropdown until it is closed.

When a dropdown is disabled, aria-disabled is set and the trigger cannot be activated. The element is removed from the tab sequence. Screen readers will announce the disabled state to the user.