claude-in-chrome: account switch (personal Max → Teams) breaks connection; reinstall fixes

## Summary

The Claude in Chrome extension worked consistently while I was signed in with a **personal Max 5x account**. After I **switched to a Teams account** — logging out on both sides (Claude Code in the terminal and claude.ai in Chrome) and logging back in with the new account — Claude Code could no longer reach Chrome at all. The extension was still installed and enabled, and Chrome was open and logged into the same account as the CLI.

**Uninstalling and reinstalling the extension fixed it immediately**, with no other change: same Chrome, same profile, same account, no Chrome restart needed beyond what the reinstall did.

This suggests the extension caches some account-scoped state at install time that is not invalidated when the signed-in account changes, leaving the pairing permanently stale.

## Steps to reproduce

1. Install the Claude in Chrome extension and use it successfully with a **personal Max 5x** account (worked fine).
2. Switch to a **Teams** account: log out of Claude Code in the terminal, log out of claude.ai in Chrome, then log back in on both with the Teams account.
3. Start a Claude Code session and ask it to use the browser.

## Expected

Claude Code connects to Chrome, as it did before the account switch.

## Actual

Every browser tool call fails to find any browser:

```
mcp__claude-in-chrome__tabs_context_mcp {createIfEmpty: true}
→ Browser extension is not connected. Please ensure the Claude browser extension
is installed and running (https://claude.ai/chrome), and that you are logged
into claude.ai with the same account as Claude Code. ...

mcp__claude-in-chrome__list_connected_browsers
→ []
```

`list_connected_browsers` returning an **empty array** is the useful detail: the extension does not merely fail to respond, it is not registered against the account at all — even though it is installed, enabled, and Chrome is signed in with that same account.

## Workaround (confirmed)

Uninstall the extension, install it again. Immediately after:

```
mcp__claude-in-chrome__list_connected_browsers
→ [{ "name": "Browser 1", "osPlatform": "macOS", "isLocal": true, ... }] # 1 device

mcp__claude-in-chrome__select_browser → Selected browser "Browser 1".
mcp__claude-in-chrome__tabs_context_mcp → tab group created
mcp__claude-in-chrome__navigate + computer(screenshot) → page rendered correctly
```

Nothing else was changed between the failing and working state.

## Environment

- Claude Code: `2.1.273`
- Google Chrome: `153.0.8010.47`
- macOS: `26.5.2` (build `25F84`)
- Extension: installed from https://claude.ai/chrome
- Account: personal Max 5x → Teams (both logged into claude.ai and Claude Code with the same account at the time of failure)

## Why this may not be a duplicate

There is a large cluster of open reports with the same *symptom* — #93991, #91145, #92668, #89913, #89482, #93473, #91959, #88232, #88558, #79985 — but I could not find one that names an **account/plan switch as the trigger**, and #79985 reports the opposite outcome (reinstall did *not* help there). If the account-switch path is the same root cause as that cluster, this issue is hopefully still useful as the reproducible trigger and a confirmed workaround.

## Suggested fix

Invalidate or re-establish the extension's device pairing when the signed-in claude.ai account changes, instead of requiring a full uninstall/reinstall. Failing that, surfacing "registered to a different account" in the error text (instead of the generic "not connected") would make this self-diagnosable — the current message sends people down the install/enable/restart path, which does not fix it.

No source files or tests are named. Start by reproducing the personal Max-to-Teams account switch, then trace the pairing state behind list_connected_browsers and tabs_context_mcp. Done means an installed extension reconnects after the account changes without requiring an uninstall and reinstall.

Written by the indexing model from the issue text.