Depending on elements and browsers, focus may not be visualized by default even if focus is received. It is a good idea to grant outline explicitly by CSS.
| Principle | Operable | User interface components and navigation must be operable. |
|---|---|---|
| Guideline | Navigable | Provide ways to help users navigate, find content, and determine where they are. |
| Criterion | Focus Visible (2.4.7 AA) |
Every user interface capable of operating the keyboard has an operation mode in which the focus indicator can be seen. |