Drop-down menus are not highlighted when selected

[per1234]

Describe the problem

In addition to the mouse, the Arduino IDE UI can be navigated using the keyboard. A UI element is first selected, then interacted with. In order to provide a visual indication of the navigation progress, the selected element should be highlighted.

🐛 Some drop-down menus are not highlighted when selected. This makes keyboard navigation of these views inconvenient.

• Boards Manager view
  • Type menu
  • version menus
• Library Manager view
  • Type menu
  • Topic menu
  • version menus
• WiFi101 / WiFiNINA Firmware Updater dialog
  • Select Board menu
  • Select firmware version
• Upload SSL Root Certificates dialog
  • Select destination board and upload certificate menu
• Serial Monitor view
  • Line ending menu
  • Baud rate menu

To reproduce

1. Press the Ctrl+Shift+I keyboard shortcut to open the "Library Manager" view.
   🙂 The first UI element of the view ("Filter your search..." field) is highlighted:
   
2. Press the Tab key to navigate to the next UI element ("Type" drop-down menu).

🐛 The UI element is not highlighted:

Expected behavior

Selected UI elements are always highlighted.

Arduino IDE version

d24a391

Operating system

Windows

Operating system version

10

Additional context

The drop-down menus in the Preferences dialog are highlighted when selected:

Issue checklist

• I searched for previous reports in the issue tracker
• I verified the problem still occurs when using the latest nightly build
• My report contains all necessary details