Shadow-root observer no longer leaks when iframes removed

1.398.7

Patch Changes

• #4113 45f17ee Thanks @TueHaulund! - fix session replay leaking a shadow-root observer when a same-origin iframe is removed

  Follow-up to the shadow-observer iframe-teardown fix: takeFullSnapshot's onSerialize registers every shadow root with the top-level document, so a root nested in a same-origin iframe was keyed to the wrong document and its observer/buffer were not disconnected when that iframe was removed (they lingered until the next full snapshot). addShadowRoot now derives the owning document from the host element, so per-document teardown matches iframe-nested roots too. (2026-07-08)