NGINX mangling rewrites when encoded URLs present

[Bob Smith]

nginx version: nginx/1.13.12

This is my rewrite:
    location / {
        rewrite  ^/(.*)$  https://example.net/$1 permanent;
    }

I am getting some really odd behavior.

For example:

mysubdomain.example.com/CL0/https:%2F%2Fapple.com

Gets re-written to

example.net/CLO/https:/apple.com

Only one forward-slash, not two before apple.com.  The original declaration was %2F%2F ?
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