A cross-origin error was thrown. React doesn‘t have access to the actual error object in development

error¶

A cross-origin error was thrown. React doesn’t have access to the actual error object in development

solution¶

I ran into this bug when I ran the react project in the morning. I saw the reason on the Internet and found that there was a problem with the package, which caused me to delete the package several times and I didn’t solve it. 

Finally, after deleting the package, use the instruction to clear the cache of the package. The package downloaded with the yarn instruction solves this problem.