Add accessible navigation to the homepage search bar

[cwbragg]

Is your feature request related to new functionality not yet included in the product? Please describe.
New. For better accessibility, make the search-bar choices (Library Search, This Site, etc) navigable with keyboard (like drop-down menus) as well as mouse.

Is your feature request related to a problem or a change to existing functionality? Please describe.
A problem - The choices are currently skipped over when using keyboard. The user can tab through the various links and menus in the nav bars above the search bar, but once they select it they can only type a query in the Library Search option.

Describe the solution you'd like
When tabbing through the nav bar options, once the user hits the search bar section, they can click the space bar or arrow keys to advance through the choices.

Describe alternatives you've considered
Either leaving it alone or simplifying the options. The hope is to make our sites the most user-friendly as possible.

How will this impact users?
Sight-impaired users who can only use keyboards will have to navigate to separate pages within the website and then to those external platforms for their searches, most typically to the Tools menu.

Example:
Homepage > Tools > Databases@emory internal website page > external databases site
Homepage > Tools > ejournals internal website page > external databases site
Homepage > Tools > Emory Digital Collections internal website page > external site
Homepage > Tools > Research Guides internal website page > external site

The Finding Aids option was rebranded ArchivesSpace, so users would need to go to:
Homepage > Tools > ArchivesSpace > external site

Articles+ doesn't appear to have its own dedicated page on the site, but could be linked from:
Materials > Articles
Tools > Library Search

Or a new Tools page created specifically for it.