Allow duplicated pre-comp layers to not affect original pre-comp layers
When duplicating pre-comped layers and adjusting the newly duplicated pre-comps attributes it automatically affects the original pre-comp as well, this for my work is irrelevant and a hassle. I would like to see it either removed or have the option to choose whether to have it affect the original layers attributes or not.

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There are a couple of different ways that you can accomplish this now.
Master Properties: https://helpx.adobe.com/after-effects/user-guide.html/after-effects/using/master-properties.ug.html
By using master properties, every time you duplicate the pre-comp, the individual properties you define in the Essential Graphics panel become independent instances. Changes to these properties are not pushed back from that single instance to the source pre-comp unless you choose to.
Copy with Property Links: https://helpx.adobe.com/after-effects/user-guide.html/after-effects/using/edit-expressions.ug.html
If you choose to copy with property links, the properties of the pasted layers will be linked to the original layer with expressions. This allows you to quickly duplicate a layer and link it's properties to the layer it was copied from.