I have the same response. I had it with lots of water but had to stop taking it after a couple of days every time I tried because it made me feel completely zoned-out. Maybe I should try again with a different brand.
Unfortunately the issue still persists and it doesn't seem to be related to caching.
I think the problem might be that NetNewsWire doesn't support SVG favicons (/y18.svg) and that /favicon.ico isn't available as a fallback. Were there any changes regarding these files recently?
is it possible that NetNewsWire (possibly other rss readers as well) don't show the favicon for https://news.ycombinator.com/rss anymore because of this change? I noticed this a few days ago