Files can be added as cards on Canvas. If two files are added as cards onto a canvas AND the files are already interlinked, then display the link on the canvas.
Why? When the files were written originally, the user found and established a conceptual connection between them. Showing the link on the canvas reminds and underscores the existing interconnection. This could be set as a toggle, e.g., “Show graph links in Canvas”, possibly configurable for each canvas file.