The most common and most likely answer to this crossword clue is the 8 letter word SPARKING
I've seen this crossword clue in The Daily Telegraph
S
P
A
R
K
I
N
G
More clues leading to the result SPARKING
Buddy explains!
The straight part
We know that "fireworks doing this" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fireworks doing this = sparking.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 SPARKING mean?
SPARKING verb- To trigger, kindle into activity (an argument, etc).
- To light; to kindle.
- To give off a spark or sparks.
- Appalachian To court.
- To woo, court; to act the gallant or beau.
- The act of producing a spark.