Duplicates are NOT being removed from history in 13.1 when
HISTCONTROL=erasedups is set.

  A value of HISTCONTROL=erasedups causes all previous lines matching the
current line to be removed from the history list before that line is saved.
(man bash)

  This isn't working on 13.1 (confirmed by others in 12.3) and I suspect it is
the case with 13.2 as well. Searching, it looks like other distros have patched
bash to insure this works when multiple terminals are open. (e.g.:
https://bugs.launchpad.net/ubuntu/+source/bash/+bug/189881)

  After moving my history file from 11.4 to 13.1 and running for close to a
year, I have close to 14,000 duplicate lines -- despite having 'erasedups' set:

  current lines: 20000 - uniq lines: 6099 = 13901 duplicates

  As a workaround, I wrote the current file out, then sorted uniquely, then
deleted the current history, read the sorted unique file in as current, and
wrote the current back to HISTFILE:

  $ history -w | sort | uniq > uniqfile
  $ history -c
  $ history -r uniqfile
  $ history -w
  $ rm uniqfile

  This is a bug and manual removal of duplicate history entries should not be
required when HISTCONTROL=erasedups is set.