Art supporter in facility left (5)
I believe the answer is:
easel
'art supporter' is the definition.
(I've seen this before)
'facility left' is the wordplay.
'facility' becomes 'ease' (I've seen this in another clue).
'left' becomes 'l' (common abbreviation).
'ease'+'l'='EASEL'
'in' acts as a link.
(Other definitions for easel that I've seen before include "supporter of board, perhaps" , "Artist's prop" , "Painting support" , "Board stanchion" , "Wooden frame for an artist" .)