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When liquids spawn, they are very messy and flow everywhere. Sometimes they remain as nonflowing source blocks, but this is not consistent at all. In particular, hot spring water from biomes o plenty never remains as a still source block.

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I can see why someone would want liquids flowing down, as it makes movement through the world much easier. Rather than disabling liquid generation altogether, a blacklist for what blocks to generate would allow me to disable liquids, and it would also let modpack makers have finer control over the world.

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making it so hot spring water does not flow on its own would also solve this problem.

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Thank you for your feedback.
As it happens, I've already worked on this not wanted behaviour and added a config option through which you can define the chance at which fluid blocks will spawn with invisible, replaceable blocks as a frame to keep them from flowing down.

This feature will be included in the soon to be released version 1.2 (Like tomorrow probably)