I run Pale Moon on Windows 10. I'm always connected to a VPN using OpenVPN. If I connect to www.example.com in Pale Moon (or any program), it uses the VPN connection. So far, so good.
However, many privacy-disrespecting websites completely block my requests or give fake error messages when trying to register accounts if they detect that the visitor doesn't want to be fully tracked (that is, if a VPN is used). For example, it's impossible to register an account on any dating website, or Github, or just about any major service at all anymore.
For this reason, I'm forced to find a way to use my "plain" home connection upon request. It's technically possible if I use a specific network interface (specified by a local IP address on Windows), so I am able to make a manual cURL request which bypasses the VPN by specifying this network interface/address for the cURL request. But that's not useful for actually browsing as a human.
Browsers/Pale Moon appears to have no such feature to specify a different network interface/address. I need to make a Pale Moon profile which always uses this network interface/address, called "Bypass VPN". But it seems impossible?
Yes, Pale Moon/browsers in general allow you to set a proxy, but not a network interface/address.
It is not an option to "disconnect the VPN" since that would break everything I'm doing through it. I only have one computer.