What does the error message "The default export is not a React Component in the page: "/" mean?

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This error message means that there is a problem with the default export in the root page (which is usually "/"). The default export (usually the last line in the file) should be a React component, but in this case it is not. It could be a simple syntax error or a problem with the component definition. This error may prevent the app from rendering properly on this page.