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Preview of Maski

Maski by Jay Thorat

Create a Maski email alias and put it in the signup form you are on. Each alias is labelled with the site you made it for, so you can see which signup a forwarded email came from.

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About this extension
Maski gives every signup its own email address. This extension creates one and fills it into the form you are looking at, so you never hand over your real address.

Why you would want this
  • A different address for every site, so when one leaks or gets sold, you know which site did it.
  • Your real address stays private. Mail sent to an alias forwards to your inbox as normal.
  • Done with one press, in the form you are already filling in, instead of a separate tab.

Each alias is labelled with the site you created it for

This is the feature the extension exists for, and it is worth being plain about what it means. When you create an alias, the hostname of the page you are on is sent to Maski and stored as that alias's label. That is what lets the extension show you "Used here" next to the address you already use on this site, rank that address first, and tell you at a glance which signup a forwarded email came from.

The label is private. Only you see it, and it never appears in mail you send or receive. If you would rather an alias carried no site label at all, create it in the Maski dashboard, where the label field is yours to fill in or leave empty.

How it works
  • Press the Maski icon in an email field, or open the popup from the toolbar.
  • The extension asks Maski for an available address and shows it to you.
  • Press again to claim it. The address is filled into the field and forwarded to your real inbox.
  • Aliases you already have appear in the list, with this site's first.

What it sends, and where

The extension talks to api.maski.dev and nothing else. There is no analytics, no telemetry, no error reporting, and no third-party request of any kind. Every font and icon is bundled, so no asset is fetched from a CDN.

It sends: your Maski API key, the alias name and domain you are registering, and the hostname of the page when you create an alias.

It does not send: your real email address, page content, form values, browsing history, or anything you type. Form fields are inspected inside the page to find where an email address goes, and none of that leaves your browser.

What it will never do

Maski will not add password filling, a vault, or form filling of any kind beyond putting a Maski alias into an email field. That is a permanent scope limit, not a roadmap gap.

What you need

A Maski account. The free plan includes 3 aliases; Pro includes 25 for $4.99 a month. Aliases forward to the address on your account, and you can reply from an alias without revealing it.

Why the extension asks for access to all sites

Signup forms are on every site, and the in-field icon has to be able to appear on the one you are using. The extension adds nothing to a page until you focus an email field, and it sends no request until you press the icon. A page with no email field costs nothing at all.
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Permissions and data

Required permissions:

  • Input data to the clipboard
  • Access your data for all web sites

Optional permissions:

  • Access your data for api.maski.dev

Required data collection, according to the developer:

  • Authentication information
  • Browsing activity
Learn more
More information
Add-on Links
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Version
1.0.0
Size
216.64 kB
Last updated
5 days ago (23 Aug 2026)
Related Categories
  • Privacy & Security
Licence
All Rights Reserved
Privacy Policy
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Version History
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Tags
  • privacy
  • security
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