Hello there, What did you do before the bug happened? (Steps to reproduce your issue) git filter-branch -f --env-filter '' --tag-name-filter cat -- HEAD What did you expect to happen? (Expected behavior) See below (difference). What happened instead? (Actual behavior) When using git filter-branch, the following message is shown: ----------8<----------------------------------------------------- WARNING: git-filter-branch has a glut of gotchas generating mangled history rewrites. Hit Ctrl-C before proceeding to abort, then use an alternative filtering tool such as 'git filter-repo' (https://github.com/newren/git-filter-repo/) instead. See the filter-branch manual page for more details; to squelch this warning, set FILTER_BRANCH_SQUELCH_WARNING=1. ----------8<----------------------------------------------------- You can suppress this by setting the environment variable shown. What's different between what you expected and what actually happened? Normally, when git introduces this kind of change, there is a git config variable that one can set to suppress it. That way one has fine grade control when to suppress it (one repo only...globally). Anything else you want to add: -/- Please review the rest of the bug report below. You can delete any lines you don't wish to share. [System Info] git version: git version 2.29.0 cpu: x86_64 no commit associated with this build sizeof-long: 8 sizeof-size_t: 8 shell-path: /bin/sh uname: Linux 4.19.0-10-amd64 #1 SMP Debian 4.19.132-1 (2020-07-24) x86_64 compiler info: gnuc: 8.3 libc info: glibc: 2.28 $SHELL (typically, interactive shell): /bin/bash