at a technical level, mothra assumed that it could display HTML in
(essentially) a single pass, because that was true
for HTML of the time.  two things happened:
	- tables were introduced, which demolished that assumption
	- graphics designers were introduced, which meant that just
	`displaying' HTML wasn't enough, it must be displayed `properly'
	which arguably can't be done well in one pass.
there's an interaction between the two because some pages
are big tables.  i did some hackery to keep mothra going for
a while, but its data structures weren't really up to the bigger tasks.
not it's fault, i hasten to add, it was just that the one pass assumption
which was true originally (and i suppose might have remained true
in a different history) no longer held so the structures were now
inappropriate.

somewhat later javascript was introduced, and as that's now fairly common
on some sites you might well like to visit, and that's even further away from
old mothra.

it gets harder and harder after that...