A lot of older posts have links such as (from post #172930) https://furaffinity.net/full/6697966 which the MD5 bot doesn't recognize as coming from FurAffinity, so it adds a link to https://www.furaffinity.net/view/6697966 . This is from the old days when clicking on an image on FA would go to a new URL to view the full image: Nowadays, FurAffinity doesn't load a new page when you click on the image, instead you stay on the page.
To work around this, perhaps there's some way to change the /full/ to /view/. I know there's some work that gets done on Pixiv links.

PR #426 would handle this, but I'm not sure what the status is.

I see that it says "1 change requested" but can't figure out which thing is still pending because the GitHub UI is so confusing sometimes.

This is constantly asked feature including many other websites for general URL sanitization, uniformation and fixing.