Event that is triggered when Page is fully rendered

Describe the problem

I need to send a signal back to a third-party server only after the ENTIRE page is fully rendered. I am a third-party library so I don't know the intricacies of any sveltekit site's architectural specifics.

I am looking for something like or to analogous to DOMContentLoaded or onload but understands SvelteKit pages and triggers after the page is fully rendered.

There are 3 candidates and each seem unsuitable:

onMount: This is close to what I need but at Page level rather than component level. I don't know the individual components in a page. I also don't know which component will be last to render (I don't know the hierarchy of components).

load: This happens before mounting.

afterNavigate: This may be what I need but the documentation doesn't make it 100% clear.

Is there a way I can inject it so that it applies at page level rather than at individual component levels?

Describe the proposed solution

Not sure. Maybe afterNavigate is what I need.

Alternatives considered

No response

Importance

i cannot use SvelteKit without it

Additional Information

No response

Start by reading the SvelteKit lifecycle entry points mentioned in the issue: onMount, load, and afterNavigate. Determine whether afterNavigate runs after a page is fully rendered and whether a page-level injection point is needed; done means the supported behavior or required API is clearly documented and verified.