JustZix

Inject CSS & JS into any page — no DevTools needed

Chrome Extensions

Productivity

Developer Tools

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Hi Product Hunt, I'm the maker of JustZix — a browser extension for saving persistent CSS and JavaScript tweaks on any website. I built it because I kept repeating the same workflow: open DevTools, paste a CSS snippet to hide a cookie wall or fix a layout, then lose it after refresh. During QA, I’d also ask developers for small changes like adding a “STAGING” badge or toggling a feature flag — things that often didn’t really need developer time. JustZix lets you attach CSS and JS to pages using URL-pattern rules, so your tweaks come back every time you visit. You can use it to: * add QA badges, warnings, toggles and quick controls * hide annoying modals, cookie walls or broken layout elements * test frontend ideas directly on real pages * debug console logs, errors, network requests and GTM dataLayer * share rule bundles with teammates using temporary short links It also brings the DevTools parts I use most directly into the tab: a CSS pane, JS pane, JS Console REPL, Output Console, live object tree, action bar, and a `window.JZ` API for scripting. A few things I care about: * free to use * no account required * no telemetry * optional sync * no email-based identity * temporary sharing links that expire in 1–48 hours JustZix is in early access and available now at justzix.com. The Chrome Web Store listing is still pending review, so the current version is distributed directly from the website. Once the store version is approved, I’ll add the official install link here. I’d love to hear what you’d use it for — QA, debugging, layout fixes, growth experiments, GTM/dataLayer work, or something completely different? Thanks for taking a look. I’ll reply to every comment today.