Follow up from https://github.com/facebook/react/pull/11616.

Here's one I found. These two invariants:

https://github.com/facebook/react/blob/7e7127387ba64f57299eaff8656542cea6fb3a2d/packages/react-reconciler/src/ReactFiberClassComponent.js#L330-L343

are in a function that's behind a DEV block:

https://github.com/facebook/react/blob/7e7127387ba64f57299eaff8656542cea6fb3a2d/packages/react-reconciler/src/ReactFiberClassComponent.js#L447-L449

I don't think this is intentional, but need to verify.

There may be more. I'll use this issue to track while https://github.com/facebook/react/pull/11616 preserves existing behavior.
it('should error reconnecting missing attributes', () =>
        expectMarkupMismatch(<div id="foo" />, <div />));
      it('should error reconnecting added attributes', () =>
        expectMarkupMismatch(<div />, <div id="foo" />));
      it('should error reconnecting different attribute values', () =>
        expectMarkupMismatch(<div id="foo" />, <div id="bar" />));
      it('can explicitly ignore errors reconnecting different element types of children', () =>
        expectMarkupMatch(
          <div>
            <div />
          </div>,
          <div suppressHydrationWarning={true}>
            <span />
          </div>,
        ));
      it('can explicitly ignore errors reconnecting missing attributes', () =>
        expectMarkupMatch(
          <div id="foo" />,
          <div suppressHydrationWarning={true} />,
        ));
      it('can explicitly ignore errors reconnecting added attributes', () =>
        expectMarkupMatch(
          <div />,
          <div id="foo" suppressHydrationWarning={true} />,
        ));
      it('can explicitly ignore errors reconnecting different attribute values', () =>
        expectMarkupMatch(
          <div id="foo" />,
          <div id="bar" suppressHydrationWarning={true} />,
        ));