https://github.com/webview/webview by zserge
A tiny cross-platform webview library for C/C++/Golang to build modern cross-platform GUIs.
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It supports two-way JavaScript bindings (to call JavaScript from C/C++/Go and to call C/C++/Go from JavaScript).
It uses Cocoa/WebKit on macOS, gtk-webkit2 on Linux and Edge on Windows 10.
I wonder if this is what Discord, etc. are using?