Trying to save a webhook causes error and is never saved

Hi,
Using 0.85.1 as a docker container and trying to create a naba webhook.

Configuration -> Automation -> +
Name: lr-light-webhook
TriggerType: webhook
Webhook id: lr-light-toggle
Actions -> action type: Call Service
Service: service.toggle
Service Data: { “entity_id”: “switch.5…1” }

Click Save causes Service system_log/write called on screen
log entry:
2019-01-13 22:05:51 ERROR (MainThread) [frontend.js.latest.201901091] http://192.168.1.4:8123/frontend_latest/a100e14d682a364a2ea6.chunk.js:1614:2063 Uncaught TypeError: Cannot read property 'attributes' of null

Google DevTools:
Console:
a100e14d682a364a2ea6.chunk.js:1614 Uncaught TypeError: Cannot read property ‘attributes’ of null
at HTMLElement.saveAutomation (a100e14d682a364a2ea6.chunk.js:1614)
at HTMLElement.handler (app-19bfb9ea.js:240)

The strangest part of all if you click on the a100e.chunk.js file … it’s a mix of JS and HTML:

        </paper-fab>
      </ha-app-layout>
    `}static get properties(){return{hass:{type:Object,observer:"_updateComponent"},narrow:{type:Boolean},showMenu:{type:Boolean,value:!1},errors:{type:Object,value:null},dirty:{type:Boolean,value:!1},config:{type:Object,value:null},automation:{type:Object,observer:"automationChanged"},creatingNew:{type:Boolean,observer:"creatingNewChanged"},isWide:{type:Boolean,observer:"_updateComponent"},_rendered:{type:Object,value:null},_renderScheduled:{type:Boolean,value:!1}}}ready(){this.configChanged=this.configChanged.bind(this);super.ready()}disconnectedCallback(){super.disconnectedCallback();if(this._rendered){Object(unmount.a)(this._rendered);this._rendered=null}}configChanged(config){if(null===this._rendered)return;this.config=config;this.errors=null;this.dirty=!0;this._updateComponent()}automationChanged(newVal,oldVal){if(!newVal)return;if(!this.hass){setTimeout(()=>this.automationChanged(newVal,oldVal),0);return}if(oldVal&&oldVal.attributes.id===newVal.attributes.id){return}this.hass.callApi("get","config/automation/config/"+newVal.attributes.id).then(function(config){["trigger","condition","action"].forEach(function(key){var value=config[key];if(value&&!Array.isArray(value)){config[key]=[value]}});this.dirty=!1;this.config=config;this._updateComponent()}.bind(this))}creatingNewChanged(newVal){if(!newVal){return}this.dirty=!1;this.config={alias:this.localize("ui.panel.config.automation.editor.default_name"),trigger:[{platform:"state"}],condition:[],action:[{service:""}]};this._updateComponent()}backTapped(){if(this.dirty&&!confirm(this.localize("ui.panel.config.automation.editor.unsaved_confirm"))){return}history.back()}async _updateComponent(){if(this._renderScheduled||!this.hass||!this.config)return;this._renderScheduled=!0;await 0;if(!this._renderScheduled)return;this._renderScheduled=!1;this._rendered=AutomationEditor(this.$.root,{automation:this.config,onChange:this.configChanged,isWide:this.isWide,hass:this.hass,localize:this.localize},this._rendered)}saveAutomation(){var id=this.creatingNew?""+Date.now():this.automation.attributes.id;this.hass.callApi("post","config/automation/config/"+id,this.config).then(function(){this.dirty=!1;if(this.creatingNew){this.navigate(`/config/automation/edit/${id}`,!0)}}.bind(this),function(errors){this.errors=errors.body.message;throw errors}.bind(this))}computeName(automation,localize){return automation?Object(compute_state_name.a)(automation):localize("ui.panel.config.automation.editor.default_name")}}customElements.define("ha-automation-editor",ha_automation_editor_HaAutomationEditor);__webpack_require__(155);class ha_automation_picker_HaAutomationPicker extends Object(localize_mixin.a)(Object(navigate_mixin.a)(polymer_element.a)){static get template(){return html_tag.a`
      <style include="ha-style">
        :host {
          display: block;
        }