I'm a big fan of the weekly roll (webtoons), a silly fun D&D comic that used to release weekly, now is a bit more sporadic but still good.
Also on the subject of sporadic D&D comics, The Order of the Stick is an extremely long running comic that is very well made and humorous.
Ended now, but Go Get a Roomie is a slice of life LGBTQ+ comic, mildly NSFW, that's fun to read and currently doing a rerun.
And as everyone else has said, XKCD is always a classic.
I recently stopped reading Questionable Content, it just feels like a mockery of what it used to be. I resisted it for a while but eventually I just couldn't take it anymore. I think my breaking point was somewhere around 1015?
As people were pointing out on Reddit, in this case I don't actually hope that, because the people who suffer as a result are the users. Tons of useful content that users have created and contributed, other people would just never have access to again.
Another example I spotted, block quotes being incorrectly parsed with newlines: