Teetotaller carrying little message (5)

I believe the answer is:

'message' is the definition.
(type of online message)

'teetotaller carrying little' is the wordplay.
'teetotaller' becomes 'tt' (abbreviation).
'carrying' means one lot of letters goes inside another.
'little' becomes 'wee' (similar in meaning).
'tt' enclosing 'wee' is 'TWEET'.

(Other definitions for tweet that I've seen before include "Birdsong" , "throwaway message?" , "Brief message" , "little message" , "Message of up to 140 characters" .)

I've seen this clue in The Sun.

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