#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
}
        public void stabilise(long stabilisationDurationMillis) {
            stabilise(stabilisationDurationMillis, false);
        }
        private void stabilise(long stabilisationDurationMillis, boolean expectIdleJoinValidationService) {
            assertThat(
                "stabilisation requires default delay variability (and proper cleanup of raised variability)",
                deterministicTaskQueue.getExecutionDelayVariabilityMillis(),
                lessThanOrEqualTo(DEFAULT_DELAY_VARIABILITY)
            );
            assertFalse("stabilisation requires stable storage", disruptStorage);
            bootstrapIfNecessary();
            runFor(stabilisationDurationMillis, "stabilising");
            
            
            
            while (clusterNodes.stream().filter(ClusterNode::deliverBlackholedRegisterRequests).count() != 0L) {
                logger.debug("--> delivering blackholed register requests");
                
                runFor(DEFAULT_DELAY_VARIABILITY * 2, "re-stabilising");
            }
            final ClusterNode leader = getAnyLeader();
            final long leaderTerm = leader.coordinator.getCurrentTerm();
            final int pendingTaskCount = leader.getPendingTaskCount();
            runFor((pendingTaskCount + 1) * DEFAULT_CLUSTER_STATE_UPDATE_DELAY, "draining task queue");
            final Matcher<Long> isEqualToLeaderVersion = equalTo(leader.coordinator.getLastAcceptedState().getVersion());
            final String leaderId = leader.getId();
            assertTrue(leaderId + " has been bootstrapped", leader.coordinator.isInitialConfigurationSet());
            assertTrue(leaderId + " exists in its last-applied state", leader.getLastAppliedClusterState().getNodes().nodeExists(leaderId));
            assertThat(