Title says it all.
I was expecting clicking an internal link to load in the same way as everything else, but my browser is refreshed as if visiting an external link.
It’s because I used the full path (Discourse Meta) rather than the relative path. However, this is how the majority of non-technical people will use links on Discourse, so my question remains.
As a side note, the full path uses one box giving a nicely formatted preview, whereas the relative path provides just the link text. What am I doing wrong?