Hi all, just wanted to share that I made a very basic plugin version of this. It just lets you specify which user field to make into a link, and—optionally—a prefix (e.g. https://mysite.com/users/). Just thought I’d share in case anyone would rather install a theme component instead of modify code. It’s based on the code in the original post in this thread.
On a side note, for my particular use case, I don’t want any user to be able to edit it; rather, I plan to update it via the discourse API. In that case, would a “custom field” be better than a “user field”? I see both in the API, but custom_fields are blank.