In https://github.com/sveltejs/svelte.dev/blob/0e0d6ed408d03a02aa009f5b16cae33516e08b48/apps/svelte.dev/content/tutorial/01-svelte/02-reactivity/04-inspecting-state/index.md it says
...you’ll see a warning, and a message saying the message could not be cloned.
However, the warning received looks like this and does not say anything about cloning:

Tested on https://svelte.dev/tutorial/svelte/inspecting-state using Microsoft Edge Version 134.0.3124.72 on Windows 11.