Interesting concept.
On latest Chrome, the "Check Fixed-Point" button appears to fail.
On latest Chrome, the "Check Fixed-Point" button appears to fail.
Of course, I know there is no guarantee that every browsers innerHTML implementation will produce exactly the same result, but so far I haven't found any variation (Chrome, FF, Safari, Edge).
EDIT: In my case, it appears to be some extra "<div style=\"position: static !important;\"></div>" text added before the closing </body> tag. I suspect this is introduced by a plugin, probably LastPass.
edit: another commenter says ad blockers are the culprit.