Making Firefox faster again

firefox-clean.sql

select count(*) from moz_historyvisits;
-- 14304

select count(*) from moz_historyvisits where visit_date >= (
    select min(visit_date) from (
        select visit_date from moz_historyvisits order by visit_date desc limit 2000
    )
);
-- 2000
-- making sure it'll work

delete from moz_historyvisits where visit_date < (
    select min(visit_date) from (
        select visit_date from moz_historyvisits order by visit_date desc limit 2000
    )
);

select count(*) from moz_historyvisits;
-- 2000
-- it worked