[inigyou]

Reddit encodes the whole thing in an opaque blob, giving you a URL like reddit.com/share/<blob> that cannot be transformed into any other format without fetching it.

[chorizo]

On a browser, you can strip the share id and post title to create a “clean” old.reddit link, with this pattern: https://old.reddit.com/r/bapcsalescanada/comments/1vd9h0j/