The idea is

  tfilter.<parent>=[handle <handle>] <tfilter> [<options>] [action [<action options>...]]

What works now:

  [tc]
  qdisc.root=handle 1234: fq_codel
  qdisc.ffff:fff1=ingress
  tfilter.1234:=matchall action drop
  tfilter.ffff:=matchall action simple sdata Hello