Is there an orthonormal basis of the Sobolev space $H^{1}(\Omega)$ with uniformly bounded elements?

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Does there exist a Hilbert (i.e., orthonormal) basis of the Sobolev space $ H^{1}(\Omega)$ with almost all bounded elements: say by 1?

Here, $\Omega$ is an open connected subset of $\mathbb{R^{3}}$.