Flash of white during startup on Windows (may possibly affect other platforms)

[fgimian]

Hey there, really great job on Rio.

On Windows, there's a rather unpleasant initial flash of white and black while the app is starting up. It may be worth keeping the window hidden until the first draw is completed.

Please see a recording below:

Cheers Fotis

[raphamorim]

Thank you for the issue!

Yes, I could reproduce it today. Will mark to take a look!

[raphamorim]

Fixed on main, it was similar issue to https://github.com/vizia/vizia/pull/386