Jumper in rubbish by river in mist (8)

I believe the answer is:

bullfrog

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

'rubbish by river in mist' is the wordplay.
'rubbish' becomes 'bull' (both can mean nonsense).
'by river' becomes 'r' (abbreviation for river. I am not sure about the 'by' bit.).
'in' means one lot of letters goes inside another.
'mist' becomes 'fog' (synonyms).
'r' placed into 'fog' is 'frog'.
'bull'+'frog'='BULLFROG'

'in' is the link.

Can you help me to learn more?

(Other definitions for bullfrog that I've seen before include "Deep-booming croaker" , "Creature with a deep croak" , "Large leaping amphibian" , "Jumper" , "Large amphibian with a deep voice" .)

I've seen this clue in The Sun.

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