I think you missed his point about how content shouldn't turn into a garbled mess of nonsense pixels just because your browser happens to be 3 months old.
True, but undefined behaviour is undefined behaviour, which is probably what's being triggered here. You can't really expect it to always be "slightly messed up but usable."
They're probably using some new APIs and didn't consider degradation at all.
Being 3 months old does not explain nonsense pixels. That's a serious bug in whatever browser the commenter is using - possibly an exploitable one since it got the browser to read from a wrong memory address.