Moving mouse out of dropdown or context menu loses focus interfering with keyboard nav

[microbit-matt-hillsdon]

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Description

dropdown-mouse-leave.mp4

Reproduction steps

1. Trigger a context menu or dropdown (via mouse is fine for reproduction, but this also applies when using the keyboard nav plugin)
2. Use up/down keys to navigate its items
3. Move the mouse across the menu without otherwise interacting with it
4. Try to continue keyboard navigation and realise focus has been lost

This is likely due to this call to blur.

At this point focus is on document.body which is unhelpful for further keyboard navigation.

Stack trace

Screenshots

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Browsers

No response

[cpcallen]

@BenHenning: Any thoughts about this, in the context of the wider work you're doing on focus? Is it reasonable to have the dropdown keep focus until it is closed?

[cpcallen]

As @microbit-matt-hillsdon noted in chat: "In some native menus [moving the mouse cursor] loses your position in the menu when you move outside but not the focus on the menu, so down arrow would start again from the top. But there might be a variety of behaviours across platforms. I would be surprised if any of them moved focus back to the start of the app though."

That is certainly my observation for how native macOS dropdowns behave. We should probably check some other platforms, but absent any significant differences that seems like a good approach that would resolve this issue.