Why set the thread as NSFW doesn't work ?

It works before for a few of my threads but today it doesn't seem like it. I tried to edit a lot of my threads as NSFW 'cause I knew that my threads possibly headlining in the sidebar. Is this a known bug ?

Edit : I set this thread as NSFW btw. But, I didn't see the confirming notification or the sign that this is now an NSFW thread