Vibe Coding Website Bugs: The 9 Problems Every AI-Built Site Ships With
Vibe coding — describing what you want and letting Lovable, Bolt.new, Replit, v0, or Claude build it — is the fastest way anyone has ever been able to ship a website. It is also the fastest way anyone has ever been able to ship bugs they don't know exist.
The pattern is always the same: the site looks finished in the builder's preview, so it feels finished. But the preview is not a real browser, not a real phone, and not a real first-time visitor. Here are the nine bugs we see most often in AI-built websites — each with a way to check for it yourself in under a minute.
The form that works for you and nobody else
You test your contact form while logged into your builder, and it works. A real visitor submits it and nothing happens — no confirmation, no email, no database row. This is the single most common vibe coding bug because the builder preview environment differs from your deployed site: environment variables not copied to production, database permissions that only allow the owner to write, or success states that render without the submission actually succeeding. How to check: open your live site in an incognito window, submit the form with a test message, then go look in your actual database or inbox. Do not trust the success message.
CTA text that vanishes on mobile
AI builders optimise for the preview pane you watch while prompting — a desktop-width view. Button text that contrasts fine on a wide layout can inherit different styles at mobile breakpoints and become invisible against its background. How to check: open your site on an actual phone (or DevTools at 375px width) and tap every button. Watch the text during the tap — hover and active states are where labels most often disappear.
Navigation links that go nowhere
Client-side routing is where AI builders most often produce something that looks right and quietly fails. Sub-menu items, footer links, and "View all" buttons frequently point to routes that were renamed in a later prompt, or to "/" as a placeholder that never got updated. How to check: click every single navigation link on the live site — including every item inside dropdowns — and confirm the page actually changes to the right destination.
The hero that eats the whole screen on mobile
A hero section sized for the desktop preview often renders at 150% or more of a phone's viewport height. Mobile visitors see a banner, and nothing else — no value proposition, no CTA — unless they scroll on faith. How to check: load your homepage on a phone. If you can't see any content or action button without scrolling, the hero needs to shrink at mobile breakpoints.
Auth that only works because you were already logged in
Sign-up and login flows generated by AI tools routinely work in the builder — where you're already authenticated — and break for genuinely new users: broken redirect URLs on the live domain, email confirmations pointing at localhost, session logic that assumes an existing cookie. How to check: incognito window, brand-new email address, complete the entire signup on the live site, including clicking the confirmation email link.
External links that hijack the visitor
Links to your LinkedIn, GitHub, or social profiles generated without target="_blank" navigate the visitor away from your site entirely. Each click on a credibility link becomes an exit. How to check: click every external link and confirm it opens in a new tab.
The logo that goes nowhere
AI builders frequently render your logo as a plain image rather than a link to the homepage. It's the first thing lost visitors click. How to check: from any inner page, click your logo. If nothing happens, it needs to be wrapped in a link to "/".
Safari: the browser your builder never showed you
Builder previews run on Chromium. Safari — which is every iPhone visitor — handles certain JavaScript events, date inputs, and CSS features differently. Drag-and-drop, custom pickers, and scroll effects that work perfectly in the preview can break completely on iOS. How to check: borrow an iPhone (or use a browser testing service) and walk through your key interactions.
Missing page titles and descriptions
Meta titles and descriptions affect nothing visible on the page, so vibe coding workflows skip them constantly. The result: your site appears in Google as "Untitled" or with a random code snippet as its description. How to check: view page source and look for the <title> tag and meta description on every key page — or run an automated scan that checks all of them at once.
Check all nine automatically
Every check above — plus about 26 more — is what QAlaunch runs automatically. Paste your URL, and a real cloud browser opens your live site on desktop and mobile, runs the full checklist plus an AI visual review, and gives you your top issues in about 2 minutes. Free, no signup.
Building with a specific platform? See the dedicated guides: testing Lovable sites, testing Bolt.new sites, Shopify store audits, and WordPress site checks.