Crossword Genius

Too often mistaken for an unimportant event (8)

Ross

I believe the answer is:

footnote

'an unimportant event' is the definition.
(a footnote in history)

'too often mistaken' is the wordplay.
'mistaken' indicates an anagram.
'too'+'often'='toooften'
'toooften' is an anagram of 'FOOTNOTE'.

'for' is the link.

(Other definitions for footnote that I've seen before include "Minor reference" , "Too often (anag.)" , "addition to manuscript" , "Comment at bottom of page" , "Explanation at bottom of page" .)

I've seen this clue in The Guardian.
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