Fix your error in 60 seconds

Plain-English fixes for the most common Lovable, Cursor, Supabase, Vercel and Next.js errors.

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• Next.jsHydration failed because the initial UI does not match what was rendered on the server
• Next.jsText content does not match server-rendered HTML
• Next.jsReferenceError: window is not defined
• Next.jsYou're importing a component that needs useState. It only works in a Client Component
• Next.jsasync/await is not yet supported in Client Components
• Next.jsModule not found: Can't resolve '...'
• Next.jsInvalid src prop on next/image, hostname is not configured
• Next.jsDynamic server usage: Route couldn't be rendered statically
• Next.jsEnvironment variable is undefined in the browser
• VercelCommand "npm run build" exited with 1
• VercelWorks locally but fails on Vercel
• VercelFUNCTION_INVOCATION_TIMEOUT (504)
• VercelFUNCTION_INVOCATION_FAILED (500)
• Vercel404: NOT_FOUND on Vercel
• Vercelnpm ERR! ERESOLVE unable to resolve dependency tree
• Supabasenew row violates row-level security policy for table
• SupabaseSupabase select returns an empty array (no error)
• SupabaseInvalid JWT / JWT expired
• SupabasesupabaseUrl is required
• Supabaserelation "public.x" does not exist
• SupabaseCould not find the column in the schema cache
• SupabaseEmail rate limit exceeded
• SupabaseTypeError: Failed to fetch (Supabase Edge Function / CORS)
• CursorCursor: model is overloaded / slow requests
• CursorCursor agent keeps making the same failed edit
• LovableLovable app shows a blank white page after deploying elsewhere
• LovableLovable/Vite: Failed to resolve import
• StripeNo signatures found matching the expected signature for payload
• StripeInvalid API Key provided
• StripeYou did not provide an API key
• StripeNo such customer: 'cus_...'
• StripeYour card was declined
• StripeAmount must be at least $0.50 usd
• Cursorcursor: command not found
• CursorExtension host terminated unexpectedly
• CursorCursor: Connection failed. Check your internet connection or VPN
• LovableTypeError: Cannot read properties of undefined (reading 'map')
• LovableEdge Function returned a non-2xx status code
• LovableUnexpected token '<', "<!DOCTYPE "... is not valid JSON
• BoltFailed to parse source for import analysis because the content contains invalid JS syntax
• BoltThe requested module does not provide an export named
• BoltToo many re-renders. React limits the number of renders to prevent an infinite loop
• ReplitError: listen EADDRINUSE: address already in use
• ReplitError: Cannot find module 'express'
• ReplitModuleNotFoundError: No module named 'flask'
• SupabaseAuthApiError: Invalid login credentials
• SupabaseAuthApiError: Email not confirmed
• Next.jsObjects are not valid as a React child
• Next.jsuseSearchParams() should be wrapped in a suspense boundary
• VercelNo Output Directory named "dist" found after the Build completed