README: drop mention of supported version

... as the intention is always to support the latest anyway

README.asciidoc

@@ -71,13 +71,25 @@ the same commits:
 % git config --global remote-hg.hg-git-compat true
 --------------------------------------
 
+****
+mnauw's note; The above is not quite the case, it only ever has been (somewhat) if
+an undocumented debug mode was enabled in `hg-git` (`debugextrainmessage` setting),
+and in recent versions the latter is no longer considered.  In fact, `hg-git` creates
+git commits with additional hg metadata stored in so-called "extra commit headers".
+The latter might be seen by `git log --format=raw` or `git cat-file -p <commitid>`,
+but are otherwise mostly used internally by the git suite (for signatures).  However,
+there is limited to no support for those in git "porcelain or plumbing" commands.
+In particular, `git fast-export` and `git fast-import` do not consider these,
+so a `gitremote-helpers` tool is then also out of luck.  Incidentally, it also
+follows that a `git fast-export | git fast-import` "clone" approach would also
+lose such extra metadata, and likewise so for e.g. `git filter-repo`.
+****
+
 == Notes ==
 
 Remember to run `git gc --aggressive` after cloning a repository, especially if
 it's a big one. Otherwise lots of space will be wasted.
 
-The newest supported version of Mercurial is 6.2, the oldest one is 2.4.
-
 === Pushing branches ===
 
 To push a branch, you need to use the 'branches/' prefix:

git-remote-hg

@@ -693,6 +693,7 @@ def export_ref(repo, name, kind, head):
                 if rename:
                     renames.append((rename[0], f))
 
+            # NOTE no longer used in hg-git, a HG:rename extra header is used
             for e in renames:
                 extra_msg += b"rename : %s => %s\n" % e
 
@@ -1127,11 +1128,17 @@ def parse_commit(parser):
         # add some extra that hg-git adds (almost) unconditionally
         # see also https://foss.heptapod.net/mercurial/hg-git/-/merge_requests/211
         # NOTE it could be changed to another value below
-        extra[b'hg-git-rename-source'] = b'git'
+        # actually, it is *almost* unconditionally, and only done if the commit
+        # is deduced to originate in git.  However, the latter is based on
+        # presence/absence of HG markers in commit "extra headers".
+        # The latter can not be handled here, and so this can not be correctly
+        # reproduced.
+        # extra[b'hg-git-rename-source'] = b'git'
         i = data.find(b'\n--HG--\n')
         if i >= 0:
             tmp = data[i + len(b'\n--HG--\n'):].strip()
             for k, v in [e.split(b' : ', 1) for e in tmp.split(b'\n')]:
+                # NOTE no longer used in hg-git, a HG:rename extra header is used
                 if k == b'rename':
                     old, new = v.split(b' => ', 1)
                     files[new]['rename'] = old

test/hg-git.t

@@ -101,6 +101,8 @@ setup () {
 	[remote-hg]
 		hg-git-compat = true
 		track-branches = false
+		# directly use local repo to avoid push (and hence phase issues)
+		shared-marks = false
 	EOF
 
 	export HGEDITOR=true