Lemma 65.16.7. Let $S$ be a scheme. If $X \to Y$ is an étale morphism of algebraic spaces over $S$, then the associated map $|X| \to |Y|$ of topological spaces is open.

Proof. This is clear from the diagram in Lemma 65.16.3 and Lemma 65.4.6. $\square$

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