Keyboard accessibility for new search bar?

Upgraded to 139.0.1 and enabled new search bar, which wasn't appearing without toggling browser.urlbar.scotchBonnet.enableOverride to true. However, the bar seems critically hindered by lack of keyboard accessibility. Two things in particular: 1) when quick actions appear (e.g., Clear recent history), I cannot figure out how to navigate to it with the keyboard. Down-arrowing simply skips over it. 2) I don't seem to be able to select which search engine to use. On Mac, Option+up/down used to select search engines with the old address bar, but no key combination seems to move through or activate the drop-down menu of search engine choices. The page introducing the feature doesn't seem to explain how to use it with keyboard at all. (https://blog.mozilla.org/en/firefox/address-bar/?utm_source=www.mozilla.org)