\section{\texorpdfstring{$\kappa$}{kappa}-extensive topology} In this appendix, $\kappa$ is a fixed infinite regular cardinal. The word `$\kappa$-small,' always means `less than $\kappa$.' % \begin{definition} % A categroy $\C$ is said to be \demph{$\kappa$-extensive} if, $\C$ admits all $\kappa$-small coproducts, for any $\kappa$-small family of objects $\{X_\lambda\}_{\lambda\in \Lambda}$, the canonical comparison functor % \[ % \C/\left({\coprod_{\lambda\in \Lambda} X_\lambda}\right) \to \prod_{\lambda\in \Lambda}\C/X_{\lambda} % \] % is an equivalence of categories. % \end{definition} \begin{definition} A categroy $\C$ is said to be \demph{$\kappa$-extensive} if, \begin{itemize} \item $\C$ admits all $\kappa$-small coproducts, \item $\C$ admits pullbacks of $\kappa$-small coproduct injection along arbitrary morphisms, and \item $\kappa$-small coproducts are disjoint and pullback stable. \end{itemize} \end{definition} In the case where $\kappa=\aleph_0$, $\aleph_0$-extensive category is simply called \demph{extensive.} Extensive categories are extensively studied in \cite{carboni1993introduction}.