cross-origin error in codesandbox since 4.0.0-beta.1

[caub]

This codesandbox https://codesandbox.io/s/lpwq74p30m works with [email protected] and below

After 4.0.0-beta.1, you get what you see currently:

A cross-origin error was thrown. React doesn't have access to the actual error object in development. See https://fb.me/react-crossorigin-error for more information.

Just reporting it in case it's a real bug, it's a bit annoying in codesandbox at least

[support]

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[joshwooding]

There's an error in the codesandbox console. I'm not sure why codesandbox reports a cross-origin error but the problem is similar to #15171 and detailed on the button page. You can see after fixing the ref forwarding the codesandbox now works: https://codesandbox.io/s/4optn

[caub]

Oh, thanks, good catch

The error is not helping, indeed