FAQ — questions and answers

Three common causes:

• Specificity — the site already has its own styles. Use !important or more specific selectors.
• Dynamic class names — frameworks generate .css-1abcd that change between versions. Target stable attributes (e.g., [data-testid="..."]) instead.
• Shadow DOM — some elements live in shadow roots and CSS from outside cannot reach them. You need JS for those.

• Check the URL pattern matches — the floating button should be visible on the page.
• JS runs once per page load — refresh the page (F5) after changing.
• Open DevTools console — errors are logged with [JustZix] prefix.
• The rule must be Enabled (just "Active" is not enough — check the toggle).

• The URL does not match any folder pattern.
• The button was hidden earlier on this page — open the popup and click Restore.
• The extension is globally disabled — toggle it in the popup.

The extension has a stable manifest key — updates preserve data. If something disappeared:

• Always update by overwriting the same folder, not by uninstalling and reinstalling.
• In chrome://extensions/, use the refresh button — never "Remove" + "Add".
• Export your settings regularly as a backup (Settings → Export).

JustZix uses chrome.scripting.executeScript to bypass CSP — works in 99% of cases. If you see CSP errors in the console, check whether the affected script is actually yours or the page's. CSP can also block inline event handlers in HTML elements you create from JS — use addEventListener instead.

Sync is fully optional. Without an account, the extension works locally in your browser only — no data leaves your machine. Sync only kicks in if you explicitly enable it and generate a sync key.

It is a 25-character key (SYNC-XXXXX-XXXXX-XXXXX-XXXXX-XXXXX) generated locally in your browser using cryptographic randomness. The backend never sees it in plain form — only its SHA-256 hash. To log in on a second device, paste the same key.

Lost it? If you previously added an email, you can recover it via Settings → Recover key. The recovery email contains a one-time link that issues a new key (the old one stops working).

You choose: 1h / 6h / 12h / 24h (default) / 48h. After expiry, the link returns 404 and the data is deleted from the backend. You can also revoke a link earlier from the "My shares" panel.

The token is a public secret — anyone with the link can download the content. Do not post it on public channels if the content is sensitive. Use shorter TTL for sensitive sets.

Without account: nothing leaves your browser.

With account (sync enabled): we store the SHA-256 hash of your sync key, your CSS/JS rules and metadata, device session info (UUID, IP, User-Agent), and optionally an email if you provide one. Full Privacy Policy →

No. The extension only reads which pages your rules apply to (URL pattern matching) — and that happens in your browser, not on our server. Browsing history is never sent anywhere.

The justzix.com website uses Google Analytics 4 only with your explicit consent (via the cookie banner). Without consent — no analytics cookies are set, no Google tag is even loaded from our pages. No Facebook Pixel, Hotjar or other third-party trackers, ever.

The extension itself collects no telemetry, no browsing history, no usage analytics — it only talks to our backend for sync/share when you explicitly enable those features.

Yes, instantly. In the extension: Settings → Account → Delete account. The backend cascades the deletion: sessions, rules, backups, shares — all gone, irreversible. Or write to support@justzix.com.

Yes, fully free. No paid plans, no premium features, no time limits. The backend has reasonable usage limits to prevent abuse (sync rate, max share size, etc.) but they comfortably cover normal use.

No firm plans. If we ever introduce paid features (e.g., team accounts, longer share TTL), the existing free tier will stay free for current functionality. We will announce changes well in advance via the Privacy Policy and Terms of Service updates.

Not currently. We may open-source parts of it after the extension is published in the Chrome Web Store and stabilizes. The backend is monorepo with the extension at github.com/0beavis0/justzix (private at the moment).

Soon — we are finalizing the Chrome Web Store release. The extension is fully functional and actively developed (recently: a rebuilt Output Console with Network and DataLayer tabs, and an interface in 8 languages). Until then, you can request an early-access ZIP for developer-mode installation: write to support@justzix.com.

Yes. JustZix now has dedicated builds for Chrome, Firefox, Edge and Opera — get each one from the download page. Other Chromium-based browsers (Brave, Vivaldi) work with the Chrome build, but are not officially tested.

From Chrome Web Store: automatic, in the background, your data persists.

Developer mode (early access): download the new ZIP, overwrite the same folder, click the refresh icon in chrome://extensions/. The extension key in the manifest is stable, so the extension ID does not change between updates.