Frank has less than twopence (4)

I believe the answer is:

open

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'frank' is the definition.
(synonyms)

'less than twopence' is the wordplay.
'OPEN' is hidden in amongst the letters.
But, I am uncertain how this is indicated.

'has' is the link.

Can you help me to learn more?

(Other definitions for open that I've seen before include "begin to > crack" , "Release" , "with no clear favourite" , "Widely known" , "Without concealment" .)

I've seen this clue in the Evening Standard.

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