diff --git a/runbot_merge/controllers/__init__.py b/runbot_merge/controllers/__init__.py
index 8b18a846..b25e9a55 100644
--- a/runbot_merge/controllers/__init__.py
+++ b/runbot_merge/controllers/__init__.py
@@ -258,7 +258,7 @@ def handle_pr(env, event):
     sender = env['res.partner'].search([('github_login', '=', event['sender']['login'])], limit=1)
     if not sender:
         sender = env['res.partner'].create({'name': event['sender']['login'], 'github_login': event['sender']['login']})
-    env.cr.precommit.data['change-author'] = sender.id
+    env['runbot_merge.pull_requests']._track_set_author(sender.id, fallback=True)
 
     if event['action'] == 'opened':
         author_name = pr['user']['login']
diff --git a/runbot_merge/models/__init__.py b/runbot_merge/models/__init__.py
index f15f98f2..ac19320c 100644
--- a/runbot_merge/models/__init__.py
+++ b/runbot_merge/models/__init__.py
@@ -1,3 +1,4 @@
+from . import mail_thread
 from . import ir_actions
 from . import res_partner
 from . import project
diff --git a/runbot_merge/models/mail_thread.py b/runbot_merge/models/mail_thread.py
new file mode 100644
index 00000000..d788e49f
--- /dev/null
+++ b/runbot_merge/models/mail_thread.py
@@ -0,0 +1,32 @@
+from collections import ChainMap
+
+from odoo import models
+from odoo.tools import ConstantMapping
+
+
+class MailThread(models.AbstractModel):
+    _inherit = 'mail.thread'
+
+    def _track_set_author(self, author, *, fallback=False):
+        """ Set the author of the tracking message. """
+        if not self._track_get_fields():
+            return
+        authors = self.env.cr.precommit.data.setdefault(f'mail.tracking.author.{self._name}', {})
+        if fallback:
+            details = authors
+            if isinstance(authors, ChainMap):
+                details = authors.maps[0]
+            self.env.cr.precommit.data[f'mail.tracking.author.{self._name}'] = ChainMap(
+                details,
+                ConstantMapping(author),
+            )
+        else:
+            for id_ in self.ids:
+                authors[id_] = author
+
+    def _message_compute_author(self, author_id=None, email_from=None, raise_on_email=True):
+        if author_id is None and self and 'id' in self:
+            t = self.env.cr.precommit.data.get(f'mail.tracking.author.{self._name}', {})
+            if len(authors := {t.get(r.id) for r in self}) == 1:
+                author_id = authors.pop()
+        return super()._message_compute_author(author_id, email_from, raise_on_email)
diff --git a/runbot_merge/models/pull_requests.py b/runbot_merge/models/pull_requests.py
index c2b243bb..b39b6681 100644
--- a/runbot_merge/models/pull_requests.py
+++ b/runbot_merge/models/pull_requests.py
@@ -954,7 +954,7 @@ For your own safety I've ignored *everything in your entire comment*.
         cmdstr = ', '.join(map(str, cmds))
         if not rejections:
             _logger.info("%s (%s) applied %s", login, name, cmdstr)
-            self.env.cr.precommit.data['change-author'] = author.id
+            self._track_set_author(author.id, fallback=True)
             return 'applied ' + cmdstr
 
         self.env.cr.rollback()
@@ -1121,27 +1121,6 @@ For your own safety I've ignored *everything in your entire comment*.
             self.env.ref('runbot_merge.check_linked_prs_status')._trigger()
         return None
 
-    def message_post(self, **kw):
-        if author := self.env.cr.precommit.data.get('change-author'):
-            kw['author_id'] = author
-        if message := self.env.cr.precommit.data.get('change-message'):
-            kw['body'] = html_escape(message)
-        return super().message_post(**kw)
-
-    def _message_log(self, **kw):
-        if author := self.env.cr.precommit.data.get('change-author'):
-            kw['author_id'] = author
-        if message := self.env.cr.precommit.data.get('change-message'):
-            kw['body'] = html_escape(message)
-        return super()._message_log(**kw)
-
-    def _message_log_batch(self, **kw):
-        if author := self.env.cr.precommit.data.get('change-author'):
-            kw['author_id'] = author
-        if message := self.env.cr.precommit.data.get('change-message'):
-            kw['bodies'] = {p.id: html_escape(message) for p in self}
-        return super()._message_log_batch(**kw)
-
     def _pr_acl(self, user):
         if not self:
             return ACL(False, False, False)
@@ -1946,6 +1925,7 @@ class Commit(models.Model):
                 self.flush(['to_check'], c)
                 if pr:
                     pr._validate(c.statuses)
+                    pr._track_set_log_message(html_escape(f"statuses changed on {sha}"))
 
                 if stagings:
                     stagings._notify(c)
@@ -1956,8 +1936,6 @@ class Commit(models.Model):
                 _logger.exception("Failed to apply commit %s (%s)", c, sha)
                 self.env.cr.rollback()
             else:
-                self.env.cr.precommit.data['change-message'] = \
-                    f"statuses changed on {sha}"
                 self.env.cr.commit()
 
     _sql_constraints = [
@@ -2199,9 +2177,8 @@ class Stagings(models.Model):
 
     def fail(self, message, prs=None):
         _logger.info("Staging %s failed: %s", self, message)
-        self.env.cr.precommit.data['change-message'] =\
-            f'staging {self.id} failed: {message}'
         prs = prs or self.batch_ids.prs
+        prs._track_set_log_message(f'staging {self.id} failed: {message}')
         prs.error = True
         for pr in prs:
            self.env.ref('runbot_merge.pr.staging.fail')._send(
@@ -2317,9 +2294,8 @@ class Stagings(models.Model):
                     'reason': str(e.__cause__ or e.__context__ or e)
                 })
             else:
-                self.env.cr.precommit.data['change-message'] =\
-                    f'staging {self.id} succeeded'
                 prs = self.mapped('batch_ids.prs')
+                prs._track_set_log_message(f'staging {self.id} succeeded')
                 logger.info(
                     "%s FF successful, marking %s as merged",
                     self, prs