> ## Documentation Index
> Fetch the complete documentation index at: https://ext.eplus.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Features

> PayPal and Stripe sandbox cards, form filling, settings, and browser support

## Payment test data

<CardGroup cols={2}>
  <Card title="Random PayPal cards" icon="credit-card">
    Generate Luhn-valid Visa, Mastercard, American Express, Diners Club, Maestro, CUP, and JCB numbers with future expiry and CVV values.
  </Card>

  <Card title="PayPal error triggers" icon="triangle-exclamation">
    Quickly exercise refused, fraud, expired, invalid, insufficient-funds, stolen-card, generic-decline, and CVV-failure paths.
  </Card>

  <Card title="Stripe scenario library" icon="stripe">
    Select predefined success, decline, and 3D Secure test cards without searching external documentation during every test.
  </Card>

  <Card title="Context-menu cards" icon="computer-mouse">
    Insert common PayPal or Stripe values directly into the last focused input field.
  </Card>
</CardGroup>

## Form automation

<CardGroup cols={2}>
  <Card title="Full-form auto-fill" icon="wand-magic-sparkles">
    Detect and fill card number, expiry, CVV, cardholder name, and country fields using common names, IDs, placeholders, and autocomplete attributes.
  </Card>

  <Card title="Framework-compatible events" icon="code">
    Dispatch native input and change events so controlled fields in React and similar applications can observe the new values.
  </Card>

  <Card title="Combined or split expiry" icon="calendar">
    Support a single expiry input as well as separate month and year inputs or select controls.
  </Card>

  <Card title="Supported development hosts" icon="globe">
    Run on PayPal, Stripe, local development hosts, and App Engine applications declared in the content-script configuration.
  </Card>
</CardGroup>

## Sidebar and customization

* Persistent side-panel workflow in Chrome.
* Firefox sidebar integration through `sidebar_action`.
* Default billing country selected from a built-in country list.
* Configurable cardholder name.
* Separate card background preferences for PayPal and Stripe.
* English and Vietnamese interfaces.

## Local storage and privacy

The extension stores user preferences through WXT's browser storage API. The current manifest requests no required Firefox data collection and does not require payment-account credentials.

<Info>
  Test card data is generated locally or selected from static sandbox values included in the extension source. The extension is designed to reduce repetitive testing input, not to process payments.
</Info>

## Browser support

| Browser | Integration                           |
| ------- | ------------------------------------- |
| Chrome  | Manifest V3 with the `sidePanel` API. |
| Firefox | Manifest V3 with `sidebar_action`.    |

## Known limitations

* Provider rules and official test-card lists can change.
* Automatic filling depends on the current page markup.
* Cross-origin secure payment iframes may block content-script access.
* The declared content script does not run on arbitrary production domains.
* Generated Luhn-valid values are not guaranteed to be accepted by a specific provider or account configuration.


## Related topics

- [ePlus.DEV Browser Extensions](/index.md)