Player-placed packed ice or generated packed ice that had its snow layers removed do not get snow generated on them when it is snowing. Snow layers can be placed manually or can fall from another block onto packed ice, but snow does not begin accumulating on the packed ice unless there is already some to begin with.
Thank you for your report!
However, this issue is Working as Intended.
The report you have submitted is working as intended: In snowy weather, snow generates on random blocks with a complete solid top surface at integer y-values, with a block light level of 9 or less, with the exception of ice and packed ice.
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Things such as graphics, sounds, world creation, biomes, redstone, villagers, and animals may not work the same in current versions.
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