How to Close Windows in Mission Control of El Capitan?

When you first trigger Mission Control you now get Desktop names rather than icons of desktops

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...which seems to be one pointless additional step, to me... however...

Once you hover over the names, they turn to icons.

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Wait half a second longer & an X appears in the corner of the one your cursor is over .

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At that point, holding Alt ⌥ will show X's over them all.

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After comments - a picture of my Mission Control settings, in case they make a difference to functionality...

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