Files with deleted suffix can be most often found as various files which had their suffix renamed, typically for semi-automatic backup reasons.
DELETED file extension - Deleted file
What is deleted file? How to open deleted files?
File type specification:
File extension deleted is used by some programs to label files, which were deleted but have been kept for backup purposes.
A .deleted file usually represents the original file with their former file extension renamed to deleted, or the deleted suffix being appended after the original one.