> ## 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.

# ePlus.DEV Browser Extensions

> Discover open-source browser tools for Gmail aliases, Google Cloud learning, and payment sandbox testing

# Browser tools built for everyday workflows

ePlus.DEV creates practical, open-source browser extensions that reduce repetitive work and keep useful controls close to the page where you need them.

This documentation covers three extensions: **Gmail Alias Toolkit** for generating and organizing Gmail aliases, **Google Cloud Skills Boost Helper** for tracking learning progress and accessing useful lab tools, and **Sandbox Pay** for testing PayPal Sandbox and Stripe card-payment scenarios.

<Info>
  These projects are independent community tools maintained by ePlus.DEV. Gmail Alias Toolkit and Google Cloud Skills Boost Helper are not affiliated with or endorsed by Google. Sandbox Pay is not affiliated with PayPal or Stripe and is intended only for sandbox and development use.
</Info>

## Explore the extensions

<CardGroup cols={3}>
  <Card title="Gmail Alias Toolkit" icon="envelope" href="/gmail-alias-toolkit/introduction">
    Generate `+tag` aliases, dot variations, random addresses, and reusable presets. Keep account-specific history, favorites, statistics, exports, QR codes, and an optional inline helper beside email fields.
  </Card>

  <Card title="Google Cloud Skills Boost Helper" icon="cloud" href="/google-cloud-skills-boost-helper/introduction">
    Track public Skills Boost profiles, estimate Arcade points, manage multiple learners, review milestones, and open solution or search actions from supported lab pages.
  </Card>

  <Card title="Sandbox Pay" icon="credit-card" href="/sandbox-pay/introduction">
    Generate PayPal Sandbox cards, select Stripe success, decline, and 3DS scenarios, trigger PayPal errors, and fill supported test payment forms from a browser sidebar.
  </Card>
</CardGroup>

## Which extension should you use?

| Your goal                                                              | Recommended extension            |
| ---------------------------------------------------------------------- | -------------------------------- |
| Create readable Gmail addresses such as `name+shopping@gmail.com`      | Gmail Alias Toolkit              |
| Generate many email variants for testing or sign-ups                   | Gmail Alias Toolkit              |
| Organize aliases with presets, favorites, history, and statistics      | Gmail Alias Toolkit              |
| Track badges and estimated Arcade progress from a public profile       | Google Cloud Skills Boost Helper |
| Manage several Skills Boost profiles with nicknames                    | Google Cloud Skills Boost Helper |
| Find a lab solution or launch a preferred fallback search              | Google Cloud Skills Boost Helper |
| Generate PayPal Sandbox card data and error cases                      | Sandbox Pay                      |
| Select Stripe success, decline, or 3D Secure test cards                | Sandbox Pay                      |
| Auto-fill card fields on supported sandbox and local development pages | Sandbox Pay                      |

## Designed around useful defaults

<CardGroup cols={2}>
  <Card title="Open source" icon="code-branch">
    Review the implementation, releases, issues, and contribution history directly on GitHub.
  </Card>

  <Card title="Privacy-aware" icon="shield-halved">
    Browser-local data is clearly separated from features that need public profiles, remote configuration, solution services, or external search providers.
  </Card>

  <Card title="Multilingual" icon="language">
    Documentation for all three extensions is available across the 12 language trees. Sandbox Pay currently provides an English and Vietnamese extension interface.
  </Card>

  <Card title="Continuously maintained" icon="arrows-rotate">
    Installation links point to official stores, release pages, or current source-build instructions instead of relying on hard-coded package files.
  </Card>
</CardGroup>

## Get started

<CardGroup cols={3}>
  <Card title="Install Gmail Alias Toolkit" icon="download" href="/gmail-alias-toolkit/installation">
    Choose Chrome Web Store, Firefox Add-ons, a GitHub release package, or a source build.
  </Card>

  <Card title="Install Skills Boost Helper" icon="download" href="/google-cloud-skills-boost-helper/installation">
    Install from a supported browser store or load a package for development and testing.
  </Card>

  <Card title="Install Sandbox Pay" icon="download" href="/sandbox-pay/installation">
    Install from Chrome Web Store or Firefox Add-ons, or build it from source for development.
  </Card>

  <Card title="Gmail Alias Toolkit source" icon="github" href="https://github.com/ePlus-DEV/gmail-alias-toolkit">
    View source code, releases, issues, and contribution guidance.
  </Card>

  <Card title="Skills Boost Helper source" icon="github" href="https://github.com/ePlus-DEV/google-cloud-skills-boost-helper">
    View source code, releases, issues, and contribution guidance.
  </Card>

  <Card title="Sandbox Pay source" icon="github" href="https://github.com/ePlus-DEV/payment-sandbox-helper">
    View source code, releases, issues, and current development status.
  </Card>
</CardGroup>

<Tip>
  Start with the extension overview, then follow its installation and usage guide. Sandbox Pay must only be used with sandbox, test-mode, or local development payment flows.
</Tip>


## Related topics

- [Installation](/sandbox-pay/installation.md)
- [FAQ](/google-cloud-skills-boost-helper/faq.md)
- [Features](/google-cloud-skills-boost-helper/features.md)
- [Google Cloud Skills Boost Helper](/google-cloud-skills-boost-helper/introduction.md)