Search results keyboard navigation doesn't scroll results

[mtalexan]

1. Open the search box in a tab
2. Search for something with more than the limit of 5 visible results
3. Use the up and down arrow keys to navigate
4. Press down until the marker goes past the bottom visible item
5. Notice the cursor navigates to something not visible in the scroll box (the box doesn't scroll)
6. Scroll to the top and off the top
7. Notice the cursor wraps to the bottom result and does scroll the scroll box
8. Navigate off the top of the visible results
9. Notice the cursor navigates to something not visible in the scroll box (the box doesn't scroll)

NOTE: this doesn't happen when using the popup, the results scroll poperly there. It only happens when the search box is opened in a tab.

Possibly related: when opening the search box in a tab and searching for something, only 5 results are ever shown in the scroll box, even if there's lots of extra space in the window below.

System:
Firefox 120.0.1
Ubuntu 22.04