Why is uvm extension limited to max 3 values?

Just out of curiosity: Why is the uvm extension [1] limited to returning no
more than 3 values? I can see how it's unlikely that more than that would
ever be needed, but it seems to me like an unnecessary limitation.

[1]: https://www.w3.org/TR/webauthn/#sctn-uvm-extension

/Emil

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Emil Lundberg

Software Developer | Yubico <http://www.yubico.com/>