What is the maximum size of a web browser's cookie's key?

Question

What is the maximum size of a web browser\'s cookie\'s key?

I know the maximum size of a cookie is 4KB, but does the key have a limitation as well?

Answer 1

Not completely entirely a direct answer to the original question, but relevant for the curious quickly trying to visually understand their cookie information storage planning without implementing a complex limiter algorithm, this string is 4096 ASCII character bytes:

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