$\DeclareMathOperator\QCoh{QCoh} \newcommand\numC{\mathbb{C}} \newcommand\numQ{\mathbb{Q}}$Let $X$ be a topological space (possibly a scheme). What happens if you apply $\QCoh$ to the prestack $(X,\underline{\numC}_{X})$, where $\underline{\numC}_{X}$ is the constant sheaf at $X$? What about $(X, \underline{\numQ}_{\ell})$?

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