LeadMax checks the features available in your browser before starting preview. Safari, iPhone and Android are not blocked simply because of their browser name.
Preview and publishing builds run in your browser through WebContainers. Agent chat and saved source files work independently, so a preview limitation does not mean your project is empty.
Browser support
| Browser | Preview and publishing |
|---|---|
| Chrome, Edge and other current desktop Chromium browsers | Supported |
| Current Firefox | Beta runtime support |
| Safari 16.4+ on macOS | Beta runtime support |
| Safari on iOS and iPadOS 16.4+ | Beta support; available device memory matters |
| Current Android Chrome and Firefox | Beta support; available device memory matters |
Use the latest browser version. Beta support can vary with project dependencies, available memory and privacy settings.
Troubleshooting
| Symptom | What to do |
|---|---|
| The editor asks to reload before starting preview | Reload the editor once to apply its browser security headers. If the message persists, open the editor directly in a normal browser tab and check extensions or privacy settings. |
| The server is ready, but its preview stays blank | Try opening the preview in a new tab. Privacy restrictions or third-party resource policies can prevent embedding; review the browser configuration guide below. |
| Shared memory or WebAssembly is unavailable | Update your browser or operating system and check whether those features are disabled. Agent chat and saved source files remain available. |
| A mobile tab reloads or stops during installation | Close unused tabs and keep the editor in the foreground. Large projects may exceed mobile memory limits; use a device with more memory for those builds. |
| Starter files are still being prepared | The editor waits for the Waku scaffold and retries automatically. If preparation pauses, open the project overview to resume. Do not create replacement files. |
| The first preview takes longer than later visits | The first launch installs project dependencies. Cached dependencies speed up later launches, but a full page reload still starts a new browser runtime. |
WebContainers browser configuration
Why reloading can help
The editor needs cross-origin isolation, shared memory and WebAssembly. Opening the editor from another page can keep the previous page's security context; a fresh load applies the editor's own headers.
Publishing uses the same browser runtime as preview. Connecting Cloudflare does not bypass a missing browser feature. Already published websites run on Cloudflare and do not require WebContainers to visit.