The default value of the IPv6 MTU of the Windows client is incorrect.

[j19981106]

I found that when the Windows client does not set the MTU value, the IPv6 MTU will be 65535. This will cause IPv6 to not work properly.

Use the `netsh interface ipv6 show subinterfaces` command to view the IPv6 MTU value.

When I checked the mailing list, I saw a question about the MTU value of Apple products, but I only saw a vague answer. Do Apple products still have this problem? Is it reasonable that the default MTU is 1420?

Mailing list regarding the MTU value of Apple products:
https://lists.zx2c4.com/pipermail/wireguard/2017-December/002201.html