Nearly do adjustment that cannot be modified (4-4)

I believe the answer is:

read-only

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'cannot be modified' is the definition.
I can't judge whether this defines the answer.

'nearly do adjustment' is the wordplay.
'adjustment' indicates an anagram (the order of letters is adjusted).
'nearly'+'do'='nearlydo'
'nearlydo' with letters rearranged gives 'READ-ONLY'.

'that' acts as a link.

Can you help me to learn more?

(Another definition for read-only that I've seen is " Like some computer memories".)

I've seen this clue in The Daily Express.

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