Most irritable from bananas not fully digested (7)

I believe the answer is:

edgiest

'most irritable' is the definition.
(I've seen this before)

'bananas not fully digested' is the wordplay.
'bananas' indicates anagramming the letters (informal term for mad).
'not fully' means to remove the last letter.
'digested' with its final letter taken off is 'digeste'.
'digeste' with letters rearranged gives 'EDGIEST'.

'from' acts as a link.

(Another definition for edgiest that I've seen is " Most irritable".)

I've seen this clue in The Independent.

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