Steps to reproduce
Following the design patterns for ComboBox as described in http://www.w3.org/TR/wai-aria-practices/#combobox
Using this implementation:
We found that Edge advertises the combobox, but also the underlying textbox separately. This causes Narrator to advertises an editing text box, but not report the combobox presence, at least not without some non-obvious exploration with the Narrator cursor.
It seems that the textbox within the combobox should be a comprehensive part of the whole, and therefore not show nested in the accessibility tree.
Comments and activity
Thank you for your report, we will take it in consideration as part of our ongoing process to improve our ARIA support.