I could have sworn mtg card links worked in comments (like Kodama of the East Tree and such)

ok, it just worked there, are they supposed to work in comments on posts on games.SE?

Any idea why they didn't work on my comment on this post: boardgames.stackexchange.com/questions/60991/…

hmm, testing here: Jace, Mirror Mage, Niko Aris

more testing: Teyo, Geometric Tactician, Minsc & Boo, Timeless Heroes

ok, let me try pasting the whole comment as a test:

At the moment, there aren't that many Planeswalkers with built-in ETB effects (I found Jace, Mirror Mage, Minsc & Boo, Timeless Heroes, Niko Aris, and Teyo, Geometric Tactician).

Other cards that trigger when a planewalker ETBs are not common either, and they typically care only about your planeswalkers (Cloudstone Curio, Yoshimaru, Ever Faithful, Kodama of the East Tree, for example). So if you are playing any of these cards, this rule is especially important.

huh, they all worked here