Combobox `inline` mode has unexpected dropdown keyboard navigation

🐛 Bug Report

When navigating the dropdown of a Combobox that has its autocomplete set to inline, then if the Combobox has its value set to something other than '', it will only navigate between items in the dropdown that match from the beginning of the current value. For example, if the value is "Sue", and there are "Sue", "Mary", and "Sue Ann" in the dropdown, a user can only navigate between "Sue" and "Sue Ann" in the dropdown, despite "Mary" being visible.

💻 Repro or Code Sample

This is an issue in the FAST Combobox implementation.

🤔 Expected Behavior

All dropdown options should be able to be selected via keyboard navigation.

😯 Current Behavior

As described, if a value has been set, keyboard navigation will skip over all options that don't match the current value text from the beginning.

💁 Possible Solution

The problem almost certainly has to do with the Combobox relying on its filteredOptions which are not being reset to the entire available options, when the autocomplete isn't set to a filter mode (either list or both).

🔦 Context

🌍 Your Environment

• OS & Device: [e.g. MacOS, iOS, Windows, Linux] on [iPhone 7, PC]
• Browser [e.g. Microsoft Edge, Google Chrome, Apple Safari, Mozilla FireFox]
• Version [e.g. 1.8.0]

Start with the FAST Combobox implementation linked in the issue and reproduce the problem using inline autocomplete with a non-empty value and options such as Sue, Mary, and Sue Ann. Inspect how filteredOptions are used during keyboard navigation. Done means every visible dropdown option can be selected with the keyboard, including options that do not match the current value from the beginning.