Ethereum-boilerplate: The ultimate full-stack

hello
I have entered this link ( https://github.com/ethereum-boilerplate/ethereum-boilerplate ) after I encountered the youtube awesome video

but unfortunately, the tutorial does not reflect reality. everything is easy in the video but right in the beginning I have seen lots of problems

for example
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Error: A cross-origin error was thrown. React doesnโ€™t have access to the actual error object in development. See https://reactjs.org/link/crossorigin-error for more information.

i tried to look search via google and other but no luck