  Stack Overflow has become an essential technical resource for developers.
However, given the vast amount of knowledge available on Stack Overflow,
finding the right information that is relevant for a given task is still
challenging, especially when a developer is looking for a solution that applies
to their specific requirements or technology stack. Clearly marking answers
with their technical context, i.e., the information that characterizes the
technologies and assumptions needed for this answer, is potentially one way to
improve navigation. However, there is no information about how often such
context is mentioned, and what kind of information it might offer. In this
paper, we conduct an empirical study to understand the occurrence of technical
context in Stack Overflow answers and comments, using tags as a proxy for
technical context. We specifically focus on additional context, where
answers/comments mention information that is not already discussed in the
question. Our results show that nearly half of our studied threads contain at
least one additional context. We find that almost 50% of the additional context
are either a library/framework, a programming language, a tool/application, an
API, or a database. Overall, our findings show the promise of using additional
context as navigational cues.
