Cryptic crossword clue
Sandwich bishop found with trace of damage round it — mouse may have moved it 6,3

The most common and most likely answer to this crossword clue is the 6 plus 3 letter word SCROLL BAR

I've seen this crossword clue in The Daily Telegraph
S
C
R
O
L
L
B
A
R

Buddy explains!

The straight part
We know that "mouse may have moved it" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case mouse may have moved it = scroll bar.
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.

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