Keep the experiment small
A prototype should answer a question. Can this layout hold a longer title? Does a control communicate its state? What happens when a click changes text? A small browser experiment can answer without a new project setup.
Codipry edits source on its main page and runs output in a sandboxed frame without same-origin privileges. Your experiment cannot read the parent's document or main-origin browser storage.
Separate source from execution
Keep markup in HTML, styling in CSS and behavior in JavaScript. The JS editor is parsed in a worker, and common loops/functions receive a best-effort execution guard. HTML inline scripts are outside that instrumenter; prefer the separate JS field.
const button = document.querySelector("#try");
button.addEventListener("click", () => {
button.textContent = "One small change.";
console.info("The experiment responded.");
});
Stop removes the frame and its timers. Run creates a fresh document rather than retaining hidden globals. The console relays bounded text diagnostics from that isolated document.
Review what someone sends you
A file or share link is untrusted source, even from a familiar person. Imports and recovered drafts load with execution paused. Read the source before Run. Keep external resources off unless the experiment needs them.
The optional resource policy allows HTTPS scripts, styles, images and fonts. Providers receive those asset requests. Fetch/XHR, nested frames and form submissions remain blocked.
Share a link, not a secret
Share data lives in a compressed fragment, outside the HTTP request to the static host. Anyone with the full link can still decode it. Never include credentials, private customer information or source you cannot share.
If the project exceeds the link limit, export JSON or ZIP. Importing a file does not upload it.
A local save is not a backup
Browser storage can be cleared by you, the browser or the operating system. Export important work. Standalone HTML is convenient for a demo; project JSON restores editable source. Use Data & Storage for a full backup across tools.
Try the starter, change one line, export and re-import. The imported version stays paused until you explicitly run it.