Allow former partner to engage in offensive old way of spreading news (8)
I believe the answer is:
teletext
'offensive old way of spreading news' is the definition.
I know nothing about this answer so I can't judge whether this works.
'allow former partner to engage in' is the wordplay.
'allow' becomes 'let' ('let' can be a synonym of 'allow').
'former partner' becomes 'ex'.
'to engage' becomes 'tet' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'in' indicates putting letters inside.
'let'+'ex'='letex'
'letex' inserted within 'tet' is 'TELETEXT'.
Can you help me to learn more?
(Other definitions for teletext that I've seen before include "'Aertel, say (8)'" , "Defunct printed news service on the box" , "TV information service" , "News information service" , "TV news service" .)