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Preview of Anonymize On-Screen Data

Anonymize On-Screen Data by mholtzmann

Swap real names, emails, phone numbers and addresses on any page for realistic fake ones, so screenshots and demos never expose anyone's data. Click to pick what to replace; it's remembered per page.

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About this extension
Take screenshots of real apps without showing real people's data.

Anonymize On-Screen Data swaps names, emails, phone numbers and addresses for realistic fakes, right on the page. Your docs, demos, bug reports and screen shares look exactly like the real thing, without exposing any personal information.

Features
  • Looks real, not redacted. Every value becomes a believable fake of the same type.
  • Consistent identities. Automatically works out when data belongs to the same person. For example, a list item would use "Elena Ortiz" for the name, "EO" for the initials, and elenaortiz@example.com for the email.
  • Choose the scope of a rule. Optionally scope any rule to "All pages", useful for elements repeated on every page like headers and footers.
  • Catches the stragglers. Replacing something like a name? The page is scanned for any other references to the original, so they all change to the same fake.
  • Set up once per page. Your picks are saved for that kind of page, so every order or customer profile anonymizes with one click, regardless of the IDs in the URL.
  • Repeatable screenshots. The same real value always gets the same fake, so a screenshot retaken next week matches the old one.
  • Stress-test your layout. "Break my layout" swaps in extra-long names and emails to show where text wraps, overflows or gets cut off.
  • A visible reminder. Optionally add a note to an existing element on the page while it's active, so nobody mistakes it for the real thing.
  • A dedicated settings page. View current rules, edit settings and manage selections.
  • Share with your team. Export your rules for teammates to import, for quick, consistent setup.

How to use
  1. Open the page you want to screenshot and click the ghost icon in the toolbar. Any rules you've saved for that page apply right away.
  2. Click Choose elements to replace (or press Alt+Shift+A), then click a name, email or other text on the page.
  3. Pick what to replace it with, e.g. Full Name, and click Apply. Every matching element changes, and the rule is saved for next time.

Reload the page or toggle it off to see the real data again. Nothing changes until you click.

Private by design

Everything runs in your browser. No accounts, no analytics, no network requests. Your rules and settings are stored locally.
Developer comments
Desktop Firefox only. The element picker needs a mouse, so Firefox for Android isn't supported.

Works on regular web pages (http and https). Firefox doesn't let add-ons change its own pages.

Fakes only change what's on your screen. Nothing on the website itself is edited or sent anywhere.

Custom options (option packs) is in beta, and its file format may change.
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Permissions and data

Required permissions:

  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Add-on Links
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Version
1.71
Size
115.88 KB
Last updated
a month ago (Oct 4, 2026)
Related Categories
  • Web Development
  • Privacy & Security
  • Appearance
License
All Rights Reserved
Version History
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Tags
  • privacy
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