#98420 verifies that the election scheduler is not running when a cluster is stable, but this assertion does not hold in the `AtomicRegisterCoordinatorTests` suite. This issue tracks the work to investigate and fix up the problem.
test/framework/src/main/java/org/elasticsearch/cluster/coordination/AbstractCoordinatorTestCase.java
final ClusterNode clusterNode = getAnyNode();
                        logger.debug("----> [runRandomly {}] rebooting [{}]", thisStep, clusterNode.getId());
                        clusterNode.close();
                        clusterNodes.forEach(cn -> deterministicTaskQueue.scheduleNow(cn.onNode(new Runnable() {
                            @Override
                            public void run() {
                                cn.transportService.disconnectFromNode(clusterNode.getLocalNode());
                            }
                            @Override
                            public String toString() {
                                return "disconnect from " + clusterNode.getLocalNode() + " after shutdown";
                            }
                        })));
                        clusterNodes.replaceAll(cn -> cn == clusterNode ? cn.restartedNode() : cn);
                    } else if (rarely()) {
                        final ClusterNode clusterNode = getAnyNode();
                        clusterNode.onNode(() -> {
                            logger.debug("----> [runRandomly {}] forcing {} to become candidate", thisStep, clusterNode.getId());
                            synchronized (clusterNode.coordinator.mutex) {
                                clusterNode.coordinator.becomeCandidate("runRandomly");
                            }
                        }).run();
                    } else if (rarely()) {
                        final ClusterNode clusterNode = getAnyNode();
                        switch (randomInt(2)) {
                            case 0:
                                if (clusterNode.heal()) {
                                    logger.debug("----> [runRandomly {}] healing {}", step, clusterNode.getId());
                                }
                                break;