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## **Description**

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Write a short description of the changes included in this pull request,
also include relevant motivation and context. Have in mind the following
questions:
1. What is the reason for the change?
2. What is the improvement/solution?
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Adds E2E tests for the Multichain API using [Metamask
Connect](connect-monorepo) (formerly SDK).

Five scenarios:
1. **Simultaneous multi-chain + Solana connection** — Verifies
`wallet_createSession` can grant 3 EVM chains + Solana scope
simultaneously and that all ScopeCards render.
2. **Per-chain `personal_sign` routing** — Confirms `personal_sign`
requests are routed to the correct chain scope and return valid
signatures.
3. **Per-chain `eth_chainId` isolation** — Validates that `eth_chainId`
returns the correct hex chain ID for each connected scope.
4. **Permission removal reflection** — Tests that removing a chain
permission via the extension UI immediately reflects in the dapp
(ScopeCard disappears).
5. **Full session termination** — Verifies `wallet_revokeSession` (via
`sdkDisconnect()`) clears session state on both dapp and wallet sides.

### New Test Dapp and Page Object
Adds the [MM Connect Test
Dapp](https://github.com/MetaMask/connect-monorepo/tree/main/playground/browser-playground)
(`test/e2e/page-objects/pages/test-dapp-mm-connect.ts`):
- The dapp exposes the MM Connect connectors.
- Replicates `@metamask/playground-ui` test ID logic in-tree for stable
selectors
- Provides clean abstraction: `selectNetworks()`, `clickConnect()`,
`triggerMethod()`, `checkMethodResult()`, `checkScopeCardVisible()`
- Handles async dialog flow correctly (trigger → approve → assert result
via `waitForSelector`)

### Infrastructure

- Added `DAPP_PATH.TEST_DAPP_MM_CONNECT` constant
- Added `MM_CONNECT_EVM_CHAINS` and `MM_CONNECT_FEATURED_CHAIN_IDS`
constants
- Added `@metamask/browser-playground@0.3.0` devDependency
- Updated `privacy-snapshot.json` with `eth.merkle.io` (RPC) and
`mm-sdk-analytics.api.cx.metamask.io` (telemetry)
- All tests use `FixtureBuilderV2`

### Privacy Changes

Adds two entries:

- **`https://eth.merkle.io`**: is the default RPC for Ethereum mainnet
chain definition at
[viem](https://github.com/wevm/viem/blob/0f7837ce96b5791b5ad45c2b2d2fe9cdabbe98b5/src/chains/definitions/mainnet.ts#L10),
the base library on top of which `wagmi` is built. `wagmi` is used by
the `browser-playground` to enable testing the new MM Connect [wagmi
connector](wevm/wagmi#4960).
- **`mm-sdk-analytics.api.cx.metamask.io`**: is the analytics endpoint
for SDK related metrics.


[![Open in GitHub
Codespaces](https://github.com/codespaces/badge.svg)](https://codespaces.new/MetaMask/metamask-extension/pull/40818?quickstart=1)
## **Changelog**

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CHANGELOG entry:

## **Related issues**

Fixes:
[WAPI-1044](https://consensyssoftware.atlassian.net/browse/WAPI-1044)

## **Manual testing steps**

1. `yarn && yarn build:test`
2. `yarn test:e2e:single test/e2e/tests/sdk/connect-multichain.spec.ts
--browser=chrome`

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

<!-- [screenshots/recordings] -->

### **After**

<!-- [screenshots/recordings] -->

## **Pre-merge author checklist**

- [x] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
- [x] I've included tests if applicable
- [x] I've documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [x] I've applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [ ] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [ ] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.


<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Medium Risk**
> Primarily adds E2E tests and test infrastructure, but introduces a new
dev dependency (`@metamask/browser-playground`) and expands the privacy
allowlist, which can affect CI stability and policy expectations.
> 
> **Overview**
> Adds a new MM Connect multichain E2E suite
(`connect-multichain.spec.ts`) that exercises `wallet_createSession`
across multiple EVM chains plus Solana, per-scope signing/`eth_chainId`,
permission removal propagation, and `wallet_revokeSession` disconnect
behavior.
> 
> Introduces a dedicated page object (`test-dapp-mm-connect.ts`) and new
E2E constants (`DAPP_PATH.TEST_DAPP_MM_CONNECT`,
`MM_CONNECT_EVM_CHAINS`, `MM_CONNECT_FEATURED_CHAIN_IDS`) to drive the
`@metamask/browser-playground` dapp, and refactors permission-page
navigation by extracting `getPermissionsPageForHost` into
`permissions.flow.ts`.
> 
> Updates test tooling/config by adding
`@metamask/browser-playground@0.3.0` to dev deps and depcheck ignores,
plus extends `privacy-snapshot.json` with `eth.merkle.io` and
`mm-sdk-analytics.api.cx.metamask.io`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
35ed097. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->



[WAPI-1044]:
https://consensyssoftware.atlassian.net/browse/WAPI-1044?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ