Silly 'nice pix' label is baffling (12)

I believe the answer is:

inexplicable

'is baffling' is the definition.
(thesaurus)

'silly nice pix label' is the wordplay.
'silly' indicates anagramming the letters.
'nice'+'pix'+'label'='nicepixlabel'
'nicepixlabel' is an anagram of 'INEXPLICABLE'.

(Another definition for inexplicable that I've seen is " Impossible to explain".)

I've seen this clue in The Irish Times.

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