Default keyboard: Focus is lost after pressing Enter on the "Close" button in the User menu

Describe the bug
When navigating using the default keyboard, focus is lost after pressing the Enter key on the "Close" button within the My Profile dialog accessed from the User menu.

Steps to reproduce the behavior:

1. Navigate to https://makecode.microbit.org/beta.
2. Sign in with a valid Microsoft account.
3. Press Tab repeatedly until focus is on the User menu button.
4. Press Enter twice to open the My Profile dialog.
5. Press Tab repeatedly until focus moves to the "Close" button.
6. Press Enter and observe the focus behavior.

Actual behavior
After pressing Enter on the "Close" button, the dialog closes but focus is lost. No visible focus indicator is present on the page.

Expected behavior
After pressing Enter on the "Close" button and closing the dialog, focus should return to the User menu button to maintain logical focus order and support accessible keyboard navigation.

Screen Recording
https://github.com/user-attachments/assets/4a24fd95-e550-4fa2-86ab-503dd21a55e0

Additional context
1.OS: Windows 11 25H2 & Mac Mini M2 macOS Tahoe 26.5
2.Browser: Chrome, Edge, Firefox, and Safari
3.makecode.microbit.org version: 8.1.17
4.Microsoft MakeCode version: 12.3.12

Start by reproducing the issue at makecode.microbit.org/beta using the User menu and My Profile dialog, then trace the keyboard handling for the dialog's Close button and User menu button. Done means pressing Enter on Close closes the dialog and visibly returns focus to the User menu button, with keyboard navigation still working.