The most common and most likely answer to this crossword clue is the 7 letter word REHANGS
I've seen this crossword clue in The Times
R
E
H
A
N
G
S
More clues leading to the result REHANGS
Buddy explains!

The straight part
We know that "New displays in gallery" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case new displays in gallery = rehangs.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does REHANGS mean?
REHANGS verb- To hang again.