I have two watched tags and 85+ ignored tags. As of checking the site today (06-09-21 PT), the process of highlighting watched tags and blurring ignored tags does not appear to be functioning the way it was previous to today.
At the top of my question display are the Newest / Active / Bountied / Unanswered / More tabs, and then just to the right of them the Filter widget. The widget is orange-lit; I don't recall it looking like that before, but it may be something I did not notice until I started looking for explanations.
It is not clear to me whether this is a bug, a change to the site (eg., new filter widget function), or my own personal settings that I have somehow changed without being aware.