Static portals to specific instances feature was mentioned on 14 September 2023 developer update, but then this segment got removed.

Tupper said: "Static portal segment’s been pulled because apparently it’s not gonna work quite that way. We’ll talk more about it later."

I just want to say: please do it the way you described in this segment. It will open up a LOT of possibilities for world creators. Personally I imagine a lot of cool ways to use this combined with remote string loading

Deleted segment itself:

Static Portal Improvement

Soon, we’ll be improving static portals to allow our creators more control over them!

Using the portal marker, you can now define an entire worldID:instanceID combo to link to a specific instance, instead of just linking to a random instance of the world. Of course, simply entering a standard wrld_id will still work. All the worlds that already use worldID static portals will continue to work like they always have.

But now, you have the option of putting in a specific instance! We’ve had a lot of cool ideas how creators might use this – emulating the old “webring” style by instance linking, creating contiguous roleplaying experiences, or even building hubs of “constant instances” where a user might go to find new communities. Combine this with Group instances so you have moderators on hand, and you’ve got a lot of opportunity to build communities in new, interesting ways!

We’re excited to see how creators employ this tiny change to link together their experiences.

Although it already may be implied, it would be nice if the developers can implement a parameter to specify the server region for those portals as well.

If we could specify instance IDs in portals, then VRChat could host (arbitrarily) large events - event beyond the 80 user cap! This sounds like a great idea.

I also have the request for VRC_PortalMarker, appending the function for jumping to the another location (maybe putting a VRC_PortalMarker) within the same instance of the world.