I am a brute force method, but I solved it myself
Method
1. Download downloadable build
2. Copy the download destination URL.
3. Edit and download the address
I use this method
"http://files.minecraftforge.net/maven/net/minecraftforge/forge/1.12-14.21.0.2338/forge-1.12-14.21.0.2338-installer.jar"
I got the above URL
4.Enjoy
This is a bad method, but it is not available for downloading normally, is not it (laugh)
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