Fix: Next.js Image Optimization Errors – Invalid src, Missing Loader, or Unoptimized
How to fix Next.js Image component errors including 'Invalid src prop', 'hostname not configured', missing loader, and optimization failures in production.
Tag: nextjs
8 articles
Fix: React useEffect runs infinitely (infinite loop / maximum update depth exceeded)
How to fix useEffect infinite loops in React — covers missing dependency arrays, referential equality, useCallback, unconditional setState, data fetching cleanup, event listeners, useRef, previous value comparison, and the exhaustive-deps lint rule.
Fix: Hydration failed because the initial UI does not match what was rendered on the server (Next.js)
How to fix the Next.js hydration mismatch error. Covers invalid HTML nesting, browser extensions, Date/time differences, useEffect for client-only code, dynamic imports, suppressHydrationWarning, localStorage, third-party scripts, Math.random, auth state, and React portals.
Fix: Loading chunk failed / ChunkLoadError
How to fix 'Loading chunk failed', 'ChunkLoadError', and 'Failed to fetch dynamically imported module' in webpack, Next.js, React, and Vite. Covers stale deployments, CDN caching, publicPath misconfiguration, service worker cache, code splitting, dynamic import retry strategies, React.lazy error boundaries, and Next.js-specific solutions.
Fix: ERR_CONNECTION_REFUSED (localhost refused to connect)
How to fix 'ERR_CONNECTION_REFUSED', 'localhost refused to connect', and 'This site can't be reached' errors when accessing localhost in Chrome, Firefox, and Edge. Covers dev servers, port issues, 0.0.0.0 vs 127.0.0.1, Docker port mapping, WSL2, firewalls, and more.
Fix: Hydration failed because the initial UI does not match what was rendered on the server
How to fix Next.js and React hydration errors including 'Text content does not match server-rendered HTML', 'Expected server HTML to contain a matching <div> in <div>', and 'There was an error while hydrating'. Covers browser extensions, Date/time mismatches, invalid HTML nesting, window checks, localStorage, and third-party components.
Fix: process.env.VARIABLE_NAME Is Undefined (Node.js, React, Next.js, Vite)
How to fix 'process.env.VARIABLE_NAME is undefined' and environment variables not loading from .env files in Node.js, React, Next.js, Vite, and Docker.
Fix: Port 3000 Is Already in Use (EADDRINUSE)
How to fix 'port 3000 is already in use', 'EADDRINUSE', and 'address already in use :::3000' errors in Node.js, React, Next.js, and other frameworks on macOS, Linux, and Windows.