  Despite the unarguable importance of Stack Overflow (SO) for the daily work
of many software developers and despite existing knowledge about the impact of
code duplication on software maintainability, the prevalence and implications
of code clones on SO have not yet received the attention they deserve. In this
paper, we motivate why studies on code duplication within SO are needed and how
existing studies on code reuse differ from this new research direction. We
present similarities and differences between code clones in general and code
clones on SO and point to open questions that need to be addressed to be able
to make data-informed decisions about how to properly handle clones on this
important platform. We present results from a first preliminary investigation,
indicating that clones on SO are common and diverse. We further point to
specific challenges, including incentives for users to clone successful answers
and difficulties with bulk edits on the platform, and conclude with possible
directions for future work.
