Hi there,
Thanks for bringing this to our attention.
List-It is still under active development (definitely not a dead
project) and we're definitely planning on supporting Firefox 4.
We're running Firefox 4.0b1 and List-It seems to work fine with it -
but nightly trunk is broken presumably because they started to
implement some of the changes listed on this page.
These changes bring about considerable complexity --particularly to
ensure that we do not break list-it for people running Firefox 3.x .
(GRR!)
If you have any experience about what changes we need to make (beyond
what is listed on the page) and are willing to help us out please let
us know :) Or know someone who can.
Otherwise I'll try to figure it out ASAP
Stay tuned..
Yours,
Max
on FF 4.0b1