Would love to see this feature working with the pdf reader in Obsidian!
(and for me it could be just the pdf in the vault)
I couldn’t get this working with external PDF-Readers on MacOS and the standard html-link-to-page approach. (They just open the file).
I think this would really add to the “link to pieces of knowledge” idea, rather than writing it down your own. With this feature you can link to specific content of external resources.
An extension of this feature, with the embedding of a pdf page in a .md file, seems interesting too, but for me the option to link to page would be enough.