Spotted on a few production instances, when you have the async notifications set up if you edit a follow up comment the notification will not sent asynchronously because the information cannot be added to the tracker_post_creation_event_log. The code is robust enough to not lost the notification but we should fix this.
[Tuleap\Tracker\Artifact\Changeset\PostCreation\ActionsRunner] Unable to queue notification for 29430, fallback to online notif: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '29430' for key 'PRIMARY':
#0 /usr/share/tuleap/src/vendor/paragonie/easydb/src/EasyDB.php(1005): PDOStatement->execute()
#1 /usr/share/tuleap/src/vendor/paragonie/easydb/src/EasyDB.php(948): ParagonIE\EasyDB\EasyDB->safeQuery()
#2 /usr/share/tuleap/plugins/tracker/include/Tracker/Artifact/Changeset/PostCreation/ActionsRunnerDao.php(32): ParagonIE\EasyDB\EasyDB->run()
#3 /usr/share/tuleap/plugins/tracker/include/Tracker/Artifact/Changeset/PostCreation/ActionsRunner.php(185): Tuleap\Tracker\Artifact\Changeset\PostCreation\ActionsRunnerDao->addNewPostCreationEvent()
#4 /usr/share/tuleap/plugins/tracker/include/Tracker/Artifact/Changeset/PostCreation/ActionsRunner.php(165): Tuleap\Tracker\Artifact\Changeset\PostCreation\ActionsRunner->queuePostCreationEvent()
#5 /usr/share/tuleap/plugins/tracker/include/Tracker/Artifact/Tracker_Artifact_Changeset.class.php(845): Tuleap\Tracker\Artifact\Changeset\PostCreation\ActionsRunner->executePostCreationActions()
#6 /usr/share/tuleap/plugins/tracker/include/Tracker/Artifact/Tracker_Artifact_Changeset.class.php(512): Tracker_Artifact_Changeset->executePostCreationActions()
#7 /usr/share/tuleap/plugins/tracker/include/Tracker/Artifact/Artifact.php(806): Tracker_Artifact_Changeset->updateComment()
#8 /usr/share/tuleap/plugins/tracker/include/Tracker/TrackerManager.class.php(111): Tuleap\Tracker\Artifact\Artifact->process()
#9 /usr/share/tuleap/plugins/tracker/include/Tracker/TrackerManager.class.php(164): TrackerManager->processSubElement()
#10 /usr/share/tuleap/plugins/tracker/include/TrackerPluginDefaultController.php(45): TrackerManager->process()
#11 /usr/share/tuleap/src/common/Request/FrontRouter.php(248): Tuleap\Tracker\TrackerPluginDefaultController->process()
#12 /usr/share/tuleap/src/common/Request/FrontRouter.php(108): Tuleap\Request\FrontRouter->routeHandler()
#13 /usr/share/tuleap/src/www/index.php(49): Tuleap\Request\FrontRouter->route()
#14 {main}