Fixed a bug with + in query

[HirbodBehnam]

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Hello
At first when getting a key value from NameValueCollection the URL will be decoded automatically. So there is no need of HttpUtility.UrlDecode.
Secondly, try to parse this ss:// URL with Import URL From Clipboard:

ss://cmM0LW1kNTpQRzh2OXpHMFJiVkJDQnpm@1.1.1.1:443?plugin=ck-client%3bUID%3dIprWshnjXx3mS3wnWsIFfcvgcvwt4%2bFcoN7%2bIBZA8nU%5c%3d%3bPublicKey%3dD9baLw4qzRhqUDWyyYvuGBTWUP5Tr0NywoB5%2bkbRtWU%5c%3d%3bServerName%3dbing.com%3bTicketTimeHint%3d3600%3bMaskBrowser%3dchrome%3bNumConn%3d4

If you go to shadowsocks server's configs and look for plugin options you will notice that there is some white spaces. This is unexpected behavior because these white spaces should be + and somehow HttpUtility.UrlDecode are replacing them with white space. So with this build I can successfully import my config without any issues.
Also you can try decoding the parameter(from ? to end) here. Notice the + signs.

[HirbodBehnam]

Plus I could not build the project unless I remove FodyWeavers.xml on Visual Studio 2019, .Net Framework 4.6.2

[celeron533]

Thank you for detecting and fixing this defect! @HirbodBehnam !