Persitance exception when saving webhook that doesn't have a trigger configured

[netwolfuk]

ERROR -   jetbrains.buildServer.SERVER - Error jetbrains.buildServer.serverSide.PersistFailedException: java.lang.NullPointerException while processing request: POST '/webhooks/ajaxEdit.html?projectId=project10&URL=http%3A%2F%2Flocalhost%3A8111%2Fwebhooks%2Fendpoint.html%3Fsomething&webHooksEnabled=on&payloadFormatHolder=none_json&BuildStarted=on&ChangesLoaded=on&BuildInterrupted=on&BeforeFinished=on&ResponsibilityChanged=on&BuildSuccessful=on&BuildFailed=on&buildTypeAll=on&buildTypeSubProjects=on&buildTypeId=bt19&buildTypeId=bt18&currentTemplateBuildId=1401&currentTemplateBuildEvent=buildSuccessful&webHookId=new&payloadFormat=json&payloadTemplate=none&submitAction=updateWebHook', from client :38862, authenticated as 'netwolfuk' {id=1} 
jetbrains.buildServer.serverSide.PersistFailedException: java.lang.NullPointerException
    at jetbrains.buildServer.serverSide.impl.projects.ProjectFileSettingsPersister.writeDocument(ProjectFileSettingsPersister.java:34)
    at jetbrains.buildServer.serverSide.impl.projects.ProjectFileSettingsPersister.saveSettings(ProjectFileSettingsPersister.java:17)
    at jetbrains.buildServer.serverSide.impl.projects.ProjectImpl.doPersistInternally(ProjectImpl.java:110)
    at jetbrains.buildServer.serverSide.impl.projects.ProjectImpl.access$300(ProjectImpl.java:724)
    at jetbrains.buildServer.serverSide.impl.projects.ProjectImpl$12$1.run(ProjectImpl.java:2)
    at jetbrains.buildServer.serverSide.impl.projects.PersistTaskImpl.run(PersistTaskImpl.java:44)
    at jetbrains.buildServer.serverSide.impl.projects.BackgroundPersisterImpl$RunTask.lambda$run$0(BackgroundPersisterImpl.java:4)
    at jetbrains.buildServer.util.NamedThreadFactory.executeWithNewThreadName(NamedThreadFactory.java:74)
    at jetbrains.buildServer.serverSide.impl.projects.BackgroundPersisterImpl$RunTask.run(BackgroundPersisterImpl.java:1)
    at jetbrains.buildServer.serverSide.impl.projects.BackgroundPersisterImpl$FlushOnDisk.run(BackgroundPersisterImpl.java:7)
    at jetbrains.buildServer.util.NamedThreadFactory.executeWithNewThreadName(NamedThreadFactory.java:74)
    at jetbrains.buildServer.util.ExceptionUtil$1.run(ExceptionUtil.java:41)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
    at webhook.teamcity.settings.WebHookConfig.getAsElement(WebHookConfig.java:294)
    at webhook.teamcity.settings.WebHookProjectSettings.writeTo(WebHookProjectSettings.java:72)
    at jetbrains.buildServer.serverSide.settings.ProjectSettingsManagerImpl.writeTo(ProjectSettingsManagerImpl.java:6)
    at jetbrains.buildServer.serverSide.impl.projects.ProjectFileSettingsPersister.writeData(ProjectFileSettingsPersister.java:13)
    at jetbrains.buildServer.serverSide.impl.projects.ProjectFileSettingsPersister.writeDocument(ProjectFileSettingsPersister.java:16)
    ... 19 more