In this example, a user has an assembly and wants to edit into a part and create a feature using geometry from another part.
The image below shows the flange on which the user wants to create the feature:
The image below shows the part with the hole from which they need to locate keypoints in order to draw a circle. 'Edge Locate' -> 'Peers' is turned ON.
However, they find that when they in-place edit into the Flange part and hit the F3 key to select the face, then try to draw the circle, they cannot pick any keypoints from the hole.
The reason this is not possible is that the in-context assembly is different from the context assembly the part is currently opened from.
If we open the part with the hole we will see in Pathfinder that its geometry has links to another part from another assembly.
We can see the edge in question - Edge 38 - on the part, below.
Currently, this is working as designed as a document can only have one context and trying to create links in another context is not supported.
NotesER#7546167 is the Master Enhancement Request to improve the Inter-Part context user Interface with this workflow. The intention would be to allow the user to locate the geometry as needed but not create a link.