The most common and most likely answer to this crossword clue is the 14 letter word BLOTTINGÂ PAPER
I've seen this crossword clue in The Guardian
B
L
O
T
T
I
N
G
Â
P
A
P
E
R
Buddy explains!
The straight part
We know that "Something found on desktop" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case something found on desktop = blotting paper.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.