Claude Code
mobile
Background Scroll Not Locked When Modal Is Open
When a modal, drawer, or overlay opens in your application, the background page continues to scroll on mobile devices. Users scrolling within the modal accidentally scroll the page behind it, losing their place. When the modal closes, the page has scrolled to a completely different position.
This is one of the most noticeable mobile UX bugs. It makes modals feel broken, confuses users, and creates a jarring experience. The issue is particularly bad on iOS Safari, which has unique scroll behavior that makes standard CSS solutions insufficient.
Claude Code typically generates modals that work well on desktop (where body overflow: hidden is sufficient) but break on mobile where touch scroll events propagate differently through the DOM.
Error Messages You Might See
Background scrolls behind modal on iPhone
Page jumps to top when modal opens
Scroll position lost after closing dialog
Cannot scroll modal content on mobile
Common Causes
- Only setting overflow: hidden on body — This works on desktop but iOS Safari ignores it for touch-initiated scrolls
- Missing position: fixed on body — Without fixing the body position, iOS allows the viewport to scroll behind overlays
- Scroll position lost on lock — Setting position: fixed resets scroll position to top; it's not restored when the modal closes
- Touch events not prevented — Touchmove events on the overlay backdrop propagate to the body
- Nested scrollable content — A scrollable area inside the modal (like a long form) conflicts with scroll prevention on the body
How to Fix It
- Use a battle-tested library — Install body-scroll-lock or use React's createPortal with scroll management from Radix UI or Headless UI
- Save and restore scroll position — Before locking, save window.scrollY. Set body to position: fixed; top: -scrollY. On unlock, restore scrollTo(0, scrollY)
- Handle iOS Safari specifically — Add -webkit-overflow-scrolling: touch to the modal content and prevent touchmove on the backdrop
- Use the dialog element — The native HTML dialog element with showModal() handles scroll locking correctly in modern browsers
- Test on real iOS devices — iOS Safari scroll behavior cannot be accurately tested in Chrome DevTools mobile simulation
Real developers can help you.
Sage Fulcher
Hey I'm Sage! Im a Boston area software engineer who grew up in South Florida. Ive worked at a ton of cool places like a telehealth kidney care startup that took part in a billion dollar merger (Cricket health/Interwell health), a boutique design agency where I got to work on a ton of exciting startups including a photography education app, a collegiate Esports league and more (Philosophie), a data analytics as a service startup in Cambridge (MA) as well as at Phillips and MIT Lincoln Lab where I designed and developed novel network security visualizations and analytics. I've been writing code and furiously devoted to using computers to make people’s lives easier for about 17 years. My degree is in making computers make pretty lights and sounds. Outside of work I love hip hop, the Celtics, professional wrestling, magic the gathering, photography, drumming, and guitars (both making and playing them)
Basel Issmail
’m a Senior Full-Stack Developer and Tech Lead with experience designing and building scalable web platforms. I work across the full development lifecycle, from translating business requirements into technical architecture to delivering reliable production systems.
My work focuses on modern web technologies, including TypeScript, Angular, Node.js, and cloud-based architectures. I enjoy solving complex technical problems and helping teams turn product ideas and prototypes into working platforms that can grow and scale.
In addition to development, I often collaborate closely with product managers, business analysts, designers, and QA teams to ensure that solutions align with both technical and business goals.
I enjoy working with startups and product teams where I can contribute both as a hands-on engineer and as a technical partner in designing and delivering impactful software.
Victor Denisov
Developer
Yovel Cohen
I got a lot of experience in building Long-horizon AI Agents in production, Backend apps that scale to millions of users and frontend knowledge as well.
Dor Yaloz
SW engineer with 6+ years of experience,
I worked with React/Node/Python
did projects with React+Capacitor.js for ios
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prajwalfullstack
Hi Im a full stack developer, a vibe coded MVP to Market ready product, I'm here to help
zipking
I am a technologist and product builder dedicated to creating high-impact solutions at the intersection of AI and specialized markets. Currently, I am focused on PropScan (EstateGuard), an AI-driven SaaS platform tailored for the Japanese real estate industry, and exploring the potential of Archify.
As an INFJ-T, I approach development with a "systems-thinking" mindset—balancing technical precision with a deep understanding of user needs. I particularly enjoy the challenge of architecting Vertical AI SaaS and optimizing Small Language Models (SLMs) to solve specific, real-world business problems. Whether I'm in a CTO-level leadership role or hands-on with the code, I thrive on building tools that turn complex data into actionable value.
Prakash Prajapati
I’m a Senior Python Developer specializing in building secure, scalable, and highly available systems. I work primarily with Python, Django, FastAPI, Docker, PostgreSQL, and modern AI tooling such as PydanticAI, focusing on clean architecture, strong design principles, and reliable DevOps practices. I enjoy solving complex engineering problems and designing systems that are maintainable, resilient, and built to scale.
Stanislav Prigodich
15+ years building iOS and web apps at startups and enterprise companies. I want to use that experience to help builders ship real products - when something breaks, I'm here to fix it.
hanson1014
Full-stack developer experienced in fixing and deploying AI-generated apps from Lovable, Bolt.new, Cursor, and Replit. I specialize in debugging Supabase integration issues (auth flows, RLS policies, database connections), fixing broken deployments, resolving routing/blank screen problems, and cleaning up messy React/Vite codebases. I also build production apps with the Claude API and have shipped a Mac desktop dev tool (Nexterm from scratch. Based in Hong Kong, fast turnaround.
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Get HelpFrequently Asked Questions
Why doesn't overflow: hidden work on iOS Safari?
iOS Safari handles touch scroll events differently from desktop browsers. Setting overflow: hidden on the body doesn't prevent touch-initiated scrolling. You need to also set position: fixed and manage the scroll position manually.
What's the simplest cross-browser scroll lock solution?
Use the body-scroll-lock npm package or the native HTML dialog element with showModal(). Both handle cross-browser scroll locking including iOS Safari edge cases.