Consider the following question: Example of R and G when $R \subseteq L(G)$ is undecidable
Is this question on-topic for cstheory? On one hand, it has been already answered on MSE and I was able to find an answer by googling "deciding if a regular language is a subset of a context-free language", while having a typical CS familiarity with the area (i.e. I am not an expert). On the other hand, asking for a specific example as well as a question that I think is not 100% straightforward to answer, so it could be useful as a reference-request question.
I noticed there are some similar questions in the meta, but nothing that IMHO is a suitable fit, especially this one. Any thoughts?