Standard for linking an annotation to another manifest

[jdchart]

Description

We have a fork of Mirador where we can link a Manifest to an annotation by appending #linked_manifest_url.json to the end of the annotation ID. (see an example here : https://coeso.tetras-libre.fr/. We're aware that this approach is not the best, and would like to implement it in the most "IIIF way" possible.

Proposed Solutions

Following chat at the av annotations birds of a feather group, the solution could be to give the annotation a motivation: linking and then have the url to the manifest as part of the annotation body. One limit to this is that it means that the annotation then noly has one function.