Regarding URL Encode/Decode of the Parameter

[m.i]

As I invetsgate more, as you pointed out, I found Nginx is working as
expected. 
It does not apply url encoding to what already has been url encoded. So,
Nginx is good. I mean, great!

We had another proxy before Nginx and it was making the url encoding issue.
Thank you for pointing out for me to see other causes.

So, again, Nginx is great!

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,275704,275720#msg-275720