[Accessibility]: Notepad screen reader issues

Created by: limitedmage

Screen reader navigation

On VoiceOver on macOS, When in the listbox in the notepad, can't use Ctrl+Opt+Left/right to move between components inside the listbox item. Only up/down arrow keys work and they move focus between the lines, but it's impossible to focus the buttons inside the listbox items.
Confirmation message not read/focused when clicking on "Remove all notes" button.

VoiceOver navigation works as expected and confirmation message is read to users and confirm button is focused after clicking the remove button.

@fkling Let me know if you can help fix this. If you still don't have a Mac device where you can run voiceover, we can reassign.

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