[Bug]: Guest messages the owner dismisses pile up on the guest page with no way to remove them #27719

Before submitting

• I searched existing issues and did not find a duplicate.
• I included enough detail to reproduce or investigate the problem.

Area

apps/web

Steps to reproduce

1. Turn on Settings > Labs > Guest links and share a thread with a guest.
2. As the guest, send a few messages.
3. As the owner, choose Dismiss on each one.
4. Look at the guest page, then reload it.

Expected behavior

The guest learns each message was not sent, and can then remove it from the page.

Actual behavior

Each dismissed message stays at the end of the guest page labeled "Not sent". Nothing removes it: no control on the message, later updates, or a reload. Each dismissal adds another one, so they pile up for as long as the tab stays open.

Cause: the guest page keeps the ids of messages it saw waiting (awaitingRowIds in apps/web/src/components/guest/guestStream.logic.ts) until a transcript row for them arrives. A dismissed message never gets a row, so it never leaves that set. The set is stored in sessionStorage (up to 50 ids), which is why a reload brings the messages back.

Impact

Minor bug or occasional failure

Version or commit

main at 028ed85

Environment

Web guest page, local dev server, Linux

Workaround

Close the tab, or open the guest link in a new one.