Two things the trace showed, one of them a wrong call on my part.
getTable() was the wrong thing to wait on. The re-apply threw "No table
set" two milliseconds after the event, meaning getTable() had already
resolved while getView() still had not -- it is the view that is missing
around a rebuild, not the table. There is no predicate for "the view is
ready", so attempt applyDepth and retry until it stops throwing, up to 5s.
And the shim matched nothing: not one callback reported a viewer. closest()
stops at a shadow boundary, so it cannot climb from an element inside
Perspective's shadow root out to the host, which is where the observed
elements live. Walk host to host via getRootNode().host instead.
The shim now also logs every callback it sees under [pf-obs], matched or
not, with a description of each target. If it still reports nothing at all,
the shim is not installed and the problem is import order rather than
matching.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The WASM engine has no notion of focus or tab visibility. It re-renders
because IntersectionObserver or ResizeObserver told it the element is
visible again at some size, and that re-render discards the view -- taking
set_depth() and per-node expansion with it, since neither lives in
ViewConfig. Listening for window 'focus' was only a guess at when that
happened, which is why the re-apply kept landing while the viewer was still
detached from its table.
Perspective's viewer captures the constructors at module-evaluation time
(`var it=window.ResizeObserver; var st=window.IntersectionObserver`), so
replacing them on window before that import puts us in front of every
callback it gets. observerShim.js does exactly that and nothing else: the
original callback runs first and unchanged, and we re-emit as a CustomEvent
only when an entry's target is or contains a perspective-viewer. That has
to be the first import in main.jsx or there is nothing left to intercept.
focus/visibilitychange/pageshow stay as a backstop for the case where the
shim could not be installed. ResizeObserver fires on every frame of a panel
drag, so observer events trail by 150ms and act once the burst settles.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
