Minecraft Classic had a test for the survival game mode available between versions 0.24 and 0.27. While the later Classic versions were creative-only, code for the survival mode still remained in the game internally.
Survival Mode re-enables survival mode on 0.30 using the game's "hidden" implementation. The mod is released as a jar built against obfuscated names for 0.30, so it won't work for other creative versions after 0.27.
To run Survival Mode, you need to install Fabric Loader alongside Classic. I don't think there's any practical installer for it currently, though, so you might need to fiddle with launcher JSON files manually.
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Juuz
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MPL-2.0
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unsupported
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