Possibly first evidence of disagreement (5)

I believe the answer is:

rifts

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'possibly first evidence of disagreement' is the definition.
I can't judge whether this definition defines the answer.

'possibly first' is the wordplay.
'possibly' 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 "Schisms" , "Breaks, severances" , "Clefts in earth, or disagreements" , "Clefts or fissures." , "Splits" .)

I've seen this clue in the Evening Standard.

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