Is it possible to put an indicator in question list to see which questions are community wiki?
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- Any Stack Exchange user can ask a question
- The community provides support, votes on ideas, and reports bugs
- Your voice helps shape the way Stack Exchange operates
This is already shown - where it would say who it was asked by and when, it says "community wiki" for CW questions. At least, it does if you're in the "questions" view rather than just the home page - I can't tell what happens on the home page as there are no CW questions there at the moment.
I think the missing bit of information there is: what problem are you trying to solve? If you don't want to "waste time" on discussion-esque questions, that should be fairly obvious from the question title.
I don't see a need for any additional UI here, personally; but if there is some purpose, feel free to elaborate...