#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
void onDisconnectEventFrom(ClusterNode clusterNode) {
                transportService.disconnectFromNode(clusterNode.localNode);
            }
            ClusterState getLastAppliedClusterState() {
                return clusterApplierService.state();
            }
            void addActionBlock(@SuppressWarnings("SameParameterValue") String actionName) {
                mockTransport.addActionBlock(actionName);
            }
            void clearActionBlocks() {
                mockTransport.clearActionBlocks();
            }
            void applyInitialConfiguration() {
                onNode(() -> {
                    final Set<String> nodeIdsWithPlaceholders = new HashSet<>(initialConfiguration.getNodeIds());
                    Stream.generate(() -> BOOTSTRAP_PLACEHOLDER_PREFIX + UUIDs.randomBase64UUID(random()))
                        .limit((Math.max(initialConfiguration.getNodeIds().size(), 2) - 1) / 2)
                        .forEach(nodeIdsWithPlaceholders::add);
                    final Set<String> nodeIds = new HashSet<>(
                        randomSubsetOf(initialConfiguration.getNodeIds().size(), nodeIdsWithPlaceholders)
                    );
                    
                    if (initialConfiguration.getNodeIds().contains(localNode.getId()) && nodeIds.contains(localNode.getId()) == false) {
                        nodeIds.remove(nodeIds.iterator().next());
                        nodeIds.add(localNode.getId());
                    }
                    final VotingConfiguration configurationWithPlaceholders = new VotingConfiguration(nodeIds);
                    try {
                        coordinator.setInitialConfiguration(configurationWithPlaceholders);
                        logger.info("successfully set initial configuration to {}", configurationWithPlaceholders);