Dull crimson was important (8)

I believe the answer is:

mattered

'was important' is the definition.
(to matter is to be important)

'dull crimson' is the wordplay.
'dull' becomes 'matte' (similar in meaning).
'crimson' becomes 'red' (synonyms).
'matte'+'red'='MATTERED'

(Other definitions for mattered that I've seen before include "Was significant" , "Counted, had significance" , "Was of importance" , "Counted, had weight" .)

I've seen this clue in the Sydney Morning Herald.

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