As always, after asking for help I find the answer: it turned out to be this Chrome flag: chrome://flags/#partition-visited-link-database-with-self-links Disabling it makes the links change color again.

Sources: https://www.reddit.com/r/bugs/comments/1f25i60/chrome_visited_links_not_changing_color/

https://github.com/tailwindlabs/tailwindcss/discussions/18150