The most common and most likely answer to this crossword clue is the 10 letter word BALUSTRADE
I've seen this crossword clue in Financial Times
B
A
L
U
S
T
R
A
D
E
More clues leading to the result BALUSTRADE
- Guard on landing party backing commerce across pond
- Rail: Labour rejected American deal
- Laboratory turning to American business an ornamental railing
- Coping with supporters a bad result upset?
- Getting jostled, but lads are coping with supporters
- Coping with supporters may produce a bad result
- Rail coach carrying the French turned over business
- Absurd tale involved a feature of terrace, perhaps
- Adults are moved behind black railing
- A bad result, collapsing row of pillars
Buddy explains!

The straight part
We know that "coping with supporters" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case coping with supporters = balustrade.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 BALUSTRADE mean?
BALUSTRADE noun- A row of balusters topped by a rail, serving as an open parapet, as along the edge of a balcony, terrace, bridge, staircase, or the eaves of a building.