Because a lot of issues lately seem to have been caused by extensions (and I'm really getting sick of typing out the disable extensions spiel), I propose we add a section to FAQ 210, probably above the "Spyware" section:
Browser Extensions - Some browser extensions may cause LiveJournal pages to display improperly. Please try using an alternate web browser with no extensions
That way, 210 is more complete and if people really do it it eliminates another cause of issues.
Another big kudos to marcelle42 for solving this :D