Suppose $X$ is compact. $A$,$B$ open sets which cover $X$. Can $X$ be covered by compact sets $C$,$D$ such that $C \subseteq A$ and $D \subseteq B$?
2026-04-29 02:39:42.1777430382
Compact refinement of a covering
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Let $X = \alpha(\mathbb{Q})$ denote the Alexandroff compactification of $\mathbb{Q}$. It is a compact non-Hausdorff $T_1$-space which is moreover a KC-space (which means that all compact subsets are closed). See the answers to https://math.stackexchange.com/q/2793610.
Now assume that $X$ satisfies the "compact refinement" property of your question. Then $X$ would be normal since it is a KC-space. But among compact $T_1$-spaces, Hausdorff is equivalent to normal. This is a contradiction.