Unfortunately, it's not possible using Devvit to determine where links like this lead to, or even if it's a post or comment that's referenced.
It'd be great if we had a way to resolve these links to the original permalink, or to a post or comment object. HTTP Fetch could theoretically be used for this (to find out where the redirect leads) but reddit.com is blocked.
About a year ago, Reddit introduced a form of link that has sharing information for easier tracking.
Example post link: https://www.reddit.com/r/unitedkingdom/s/i1ISuc5IKa
Unfortunately, it's not possible using Devvit to determine where links like this lead to, or even if it's a post or comment that's referenced.
It'd be great if we had a way to resolve these links to the original permalink, or to a post or comment object. HTTP Fetch could theoretically be used for this (to find out where the redirect leads) but reddit.com is blocked.