Issue Summary

The element appears and functions like an Autocomplete Combobox but is missing the required ARIA role(s) and/or attribute(s).
Element Name: Destination Combobox

Steps to Reproduce

1. Launch the URL 
2. Navigate to the "Show more pull request actions" and activate it.
3. Activate the "Edit" option from the dropdown menu and a modal will popup.
4. Navigate to the Destination dropdown menu.

Screenshot

Actual Results

In the Edit pull request, the modal contains a autocomplete Combobox for the "Destination" input field. These particular elements have some of the Labels and Roles missing. When native HTML elements are used basic information about an element, such as name, role, state and value are exposed to assistive technologies by default. However, for custom components, this information needs to be made available for assistive technologies, so users can interact with the custom components effectively.

Expected Results

Few of the following labels and roles could be added to the following elements :

• A role="combobox" could be added to the <div> element.
• The dropdown menu should announce the label it is associated with.
• For this case, when the users focus to enter the Dropdown menu, it should announce content such as "Destination, select the Destination for the Branch". This will help the assistive technology user to understand the relation between the label and the dropdown menu.
• A working example for accessible Autocomplete Combobox could be found at: https://www.w3.org/WAI/ARIA/apg/example-index/combobox/combobox-autocomplete-both.html 

Workaround

Currently, there is no known workaround for this behaviour. A workaround will be added here when available.

Bug Ref: 742045