Differences need sorting out first (5)

I believe the answer is:

rifts

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'differences need sorting' is the definition.
I can't tell whether this defines the answer.

'out first' is the wordplay.
'out' indicates an anagram.
'first' with letters rearranged gives 'RIFTS'.

Can you help me to learn more?

(Other definitions for rifts that I've seen before include "Breaks, severances" , "differences ..." , "Splits" , "Clefts or fissures." , "Deep divides" .)

I've seen this clue in The Globe and Mail.

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