Doesn't look like you can supply your own blocklist. By design perhaps, because Google.
post
Nice. a milktoast ad blocker
replies:
As such, it might not have turned up for every user just yet.
But I want it now :(
1 comment in c/firefox@fedia.io view that post
I asked on Mozilla Connect if it is possible to add additional filter lists, but I got no response.
all 7 comments