Error when displaying an HTML page with ReactJS

[Igor Tautul]

  Hi,

I can't display an HTML page that contains a complex 3D visualization in a Tkinter frame.

I get a JavaScript error about: .flatMap is not a function. From what I found on the forums, in general, it is a problem of NodeJS version, if it is less than 11, there it does not exist.

The HTML page with this 3D view, is well displayed in all browsers, including latest version of Chromium. 

I would need help, at least with some advice, because although the application is written entirely in python, it has gone too far, and to change something would hurt too much. :) 

Thank you very much for your time and cefpython3. :) 

[Czarek Tomczak.]

Check all output in Developer Tools console. The cause is probably an old version of Chromium embedded, cefpython v66 includes Chromium 66.