React

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Uncaught Error: Module build failed (from ./node_modules/babel-loader/lib/index.js): Error: Cannot find module '@babel/core'

ValidationError: Invalid options object. Sass Loader has been initialized using an options object that does not match the API schema. 또는 Uncaught Error: Module build failed (from ./node_modules/sass-loader/dist/cjs.js): ... CORS

Attempted import error: 'dafault' is not exported from '경로'.

./src/components/common/Header/Header.scss (./node_modules/css-loader/dist/cjs.js??ref--6-oneOf-5-1!./node_modules/postcss-loader/src??postcss!./node_modules/sass-loader/lib/loader.js??ref--6-oneOf-5-3!./src/components/common/Header/Header.scss)
@import "lib/all";
^
File to import not found or unreadable: lib/all.
in D:\Files\study\project\blog\blog-frontend\src\styles\utils.scss (line 1, column 1)

Add @babel/plugin-proposal-class-properties (https://git.io/vb4SL) to the 'plugins' section of your Babel config to enable transformation.
If you want to leave it as-is, add @babel/plugin-syntax-class-properties (https://git.io/vb4yQ) to the 'plugins' section to enable parsing.

Crossorigin error, 크로스오리진

Context API dispatch Action 무반응!!!! 오류는 없지만 작동은 안 되는..

Uncaught ReferenceError: React is not defined

Access to XMLHttpRequest at 'http://openapi.epost.go.kr/postal/오픈API링크' from origin 'http://localhost:3000' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

form submission canceled because the form is not connected

img is a void element tag and must neither have children nor use dangerouslySetInnerHTML.

동시에 발생
The above error occurred in the <div> component
index.js:1 Warning: React.createElement: type is invalid -- expected a string (for built-in components) or a class/function (for composite components) but got: undefined. You likely forgot to export your component from the file it's defined in, or you might have mixed up default and named imports.
Uncaught Error: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: undefined. You likely forgot to export your component from the file it's defined in, or you might have mixed up default and named imports.

img elements must have an alt prop, either with meaningful text, or an empty string for decorative images

별다른 에러 뜨는 건 없는데 아무리 찾아봐도 데이터가 없다면

Next.js

useHref() may be used only in the context of a <Router> component.

next Typescript Function component is not a function declaration

PWA

공통(?)

Unhandled Runtime Error
Error: Hydration failed because the initial UI does not match what was rendered on the server.
See more info here: https://nextjs.org/docs/messages/react-hydration-error

ES6, nodejs 버전 차이?
require와 import 충돌 문제