There's a merged pull request on the void-packages repository

xorg-server: needs libxshmfence-devel
https://github.com/void-linux/void-packages/pull/34043

Description:
otherwise the build fails; it’s missing due to https://github.com/void-linux/void-packages/commit/32b3f0eab82a52fa37bef1a26a9a8d2afd6ccc92

@q66

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