Issues with Dynamic Route and initialCanonicalUrl Property

[cameronsb]

Hi there!

I have a project that uses a Dynamic Route in the App Router - for example, /resource/edit/[id]/page.js.

There are 2 issues occurring, both of which seem to be related.

1. When the page is loaded, there is a failed request made to mysite.com/resource/edit/123/null.

2. There's a sidebar with a "back" button (which is actually just updating the UI rather than navigating). When clicking the "back" button, there is always a request for mysite.com/resource/edit/123/undefined.

Given the workflow of the app, these 404s clog up the console and make it seem like something is broken, but I'm not sure where the behavior is coming from.

---

After digging into the document, both of these values are defined internally by the initialCanonicalUrl property.
"initialCanonicalUrl: "/resource/edit/123/null/", ...

I've seen this property mentioned here:
#58357

However, it's not quite the same issue.

I can provide more details as needed, but I'm wondering if there's a way to troubleshoot/tweak the value that is ultimately used as the initialCanonicalUrl value, since I haven't found it anywhere in the docs.

Thanks!