[PATCH 4/4] doc: v1: add a reference to git-filter-repo(1), too

[Eric Wong <e@yhbt.net>]

The git-filter-branch(1) manpage itself recommends git-filter-repo,
nowadays due to performance and safety problems.
---
 Documentation/public-inbox-v1-format.pod | 3 ++-
 Documentation/txt2pre                    | 2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/Documentation/public-inbox-v1-format.pod b/Documentation/public-inbox-v1-format.pod
index 507c9451..47a6c94a 100644
--- a/Documentation/public-inbox-v1-format.pod
+++ b/Documentation/public-inbox-v1-format.pod
@@ -169,7 +169,8 @@ there may be many files.
 
 It is impossible to completely expunge messages, even spam, as git
 retains full history.  Projects may (with adequate notice) cycle to new
-repositories/branches with history cleaned up via L<git-filter-branch(1)>.
+repositories/branches with history cleaned up via L<git-filter-repo(1)>
+or L<git-filter-branch(1)>.
 This is up to the administrators.
 
 =head1 COPYRIGHT
diff --git a/Documentation/txt2pre b/Documentation/txt2pre
index 01b49379..e058125a 100755
--- a/Documentation/txt2pre
+++ b/Documentation/txt2pre
@@ -77,6 +77,8 @@ $xurls{'spamc(1)'} =
 $xurls{'grok-pull'} =
 	'https://git.kernel.org/pub/scm/utils/grokmirror/grokmirror.git' .
 	'/tree/man/grok-pull.1.rst';
+$xurls{'git-filter-repo(1)'} = 'https://github.com/newren/git-filter-repo'.
+			'./blob/master/Documentation/git-filter-repo.txt';
 $xurls{'ssoma(1)'} = 'https://ssoma.public-inbox.org/ssoma.txt';
 $xurls{'cgitrc(5)'} = 'https://git.zx2c4.com/cgit/tree/cgitrc.5.txt';