tab-new crashes in attach --extension sessions with TypeError reading _page

[jianzhangg]

Summary

tab-new fails in an attach --extension=msedge session with:

TypeError: Cannot read properties of undefined (reading '_page')

This does not reproduce in a normal open session on the same machine.

Version

• @playwright/cli: 0.1.8
• OS: macOS 15.7.4
• Browser: Microsoft Edge (attached via extension)

Repro

1. Attach to a running Edge session via extension:

playwright-cli -s=pf attach --extension=msedge

2. Confirm the session is alive:

playwright-cli -s=pf tab-list

Example output:

### Result
- 0: (current) [森果云-批发易](http://pfzone.senguo.me:3009/easy/private/salesman)

3. Try to create a new tab:

playwright-cli -s=pf tab-new

or:

playwright-cli -s=pf tab-new 'http://pfzone.senguo.me:3009/easy/private/salesman'

Actual result

Both commands fail immediately with:

### Error
TypeError: Cannot read properties of undefined (reading '_page')

Expected result

tab-new should create a new tab in the attached session, the same way it does in a normal open session.

Control case

The same command works in a non-attach session:

playwright-cli -s=cmp open --browser=msedge 'http://pfzone.senguo.me:3009/easy/private/salesman'
playwright-cli -s=cmp tab-new
playwright-cli -s=cmp tab-new 'http://pfzone.senguo.me:3009/easy/private/salesman'

In that case, new tabs are created successfully.

Notes

• I also tried attach --cdp=msedge, but on this machine remote debugging was not enabled, so I could not compare CDP attach behavior yet.
• This looks specific to attach --extension rather than a general tab-new failure.