They display art in moderate sizes (6)

I believe the answer is:

easels

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'they display art' is the definition.
(easels hold paintings)

'moderate sizes' is the wordplay.
'moderate' becomes 'ease' (I've seen this in another clue).
'sizes' becomes 'ls' (I can't justify this - if you can you should believe this answer much more).
'ease'+'ls'='EASELS'

'in' acts as a link.

Can you help me to learn more?

(Other definitions for easels that I've seen before include "Painters' stands" , "Supports in the studio" , "Leases (anag)" , "Supports for paintings" , "Artists' supports" .)

I've seen this clue in The Telegraph.

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