Use this and all's well, presumably (7)

I believe the answer is:

cureall

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'well presumably' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'use this and all's' is the wordplay.
'use' becomes 'cure' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'this and' is a charade indicator (letters next to each other).
'cure'+'all'='CUREALL'

Can you help me to learn more?

I've seen this clue in The Irish News and The Guardian.

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