diff --git a/public/manifest.json b/public/manifest.json
index 6f6dfd7..2acfd42 100644
--- a/public/manifest.json
+++ b/public/manifest.json
@@ -24,6 +24,7 @@
       "Icon": "images/actionImage",
       "Name": "Entity (custom icons)",
       "PropertyInspectorPath": "pi.html",
+      "DisableAutomaticStates": true,
       "States": [
         {
           "Image": "images/ha-button-off",
diff --git a/src/components/ServiceCallConfiguration.vue b/src/components/ServiceCallConfiguration.vue
index 9200910..f30a14f 100644
--- a/src/components/ServiceCallConfiguration.vue
+++ b/src/components/ServiceCallConfiguration.vue
@@ -71,10 +71,10 @@
       <details v-if="dataProperties && dataProperties.length > 0">
         <summary>Available options</summary>
         <div v-for="item in dataProperties" v-bind:key="item.name" class="form-text">
-          <span class="text-info font-monospace">{{ item.name }}&nbsp;</span>{{ item.info.description }}
+          <span class="text-info font-monospace">{{ item.name }}&nbsp;</span> <span class="text-warning font-monospace" v-if="item.info.required">(required) </span>{{ item.info.description }}
           <template v-if="item.info.example">
             <br>
-            <span  class="ml-2">Example: <i>{{ item.info.example }}</i></span>
+            <span class="ml-2">Example: <i>{{ item.info.example }}</i></span>
           </template>
         </div>
       </details>
@@ -156,8 +156,10 @@ const domainEntities = computed(() => {
     return [];
   }
   let selectedService = props.availableServices.filter(service => service.serviceId === props.modelValue.serviceId)[0]
-  if (selectedService && selectedService.target && Array.isArray(selectedService.target.entity)) {
-    let targetDomains = selectedService.target.entity.filter(entity => entity.domain).flatMap(entity => entity.domain);
+  if (selectedService && selectedService.target && selectedService.target.entity) {
+    // target.entity may contain a single or an array of entities. Make sure we always work with array.
+    let targetEntities = ensureArray(selectedService.target.entity);
+    let targetDomains = targetEntities.filter(entity => entity.domain).flatMap(entity => ensureArray(entity.domain));
     if (targetDomains.length > 0) {
       return props.availableEntities.filter(entity => targetDomains.includes(entity.domain)).sort(titleSort);
     } else {
@@ -173,7 +175,11 @@ const serviceDataInvalidFeedback = computed(() => {
     return "";
   }
   try {
-    const renderedServiceData = nunjucks.renderString(serviceDataString, {ticks: 5, rotationPercent: 100, rotationAbsolute: 100});
+    const renderedServiceData = nunjucks.renderString(serviceDataString, {
+      ticks: 5,
+      rotationPercent: 100,
+      rotationAbsolute: 100
+    });
 
     const json = JSON.parse(renderedServiceData);
     return (typeof json === "object") ? "" : "Service data must be an JSON object."
@@ -199,4 +205,8 @@ const dataProperties = computed(() => {
 
 })
 
+function ensureArray(input) {
+  return Array.isArray(input) ? input : [input];
+}
+
 </script>
diff --git a/src/modules/homeassistant/actions/service-action.js b/src/modules/homeassistant/actions/service-action.js
index b53f2e1..e0af640 100644
--- a/src/modules/homeassistant/actions/service-action.js
+++ b/src/modules/homeassistant/actions/service-action.js
@@ -22,15 +22,17 @@ export class ServiceAction extends Action {
     if (typeof service !== 'string' || !service.trim()) {
       throw new Error('Service must be a non-empty string')
     }
-    if (!Array.isArray(entity_id)) {
+    if (entity_id && !Array.isArray(entity_id)) {
       throw new TypeError('entity_id must be an array')
     }
     if (typeof serviceData !== 'object' || serviceData === null) {
       throw new TypeError('serviceData must be an object')
     }
+    if (entity_id) {
+      this.target = {entity_id: entity_id}
+    }
 
     this.service = `${domain}.${service}`
     this.data = serviceData
-    this.target = { entity_id: entity_id }
   }
 }
diff --git a/src/modules/homeassistant/homeassistant.js b/src/modules/homeassistant/homeassistant.js
index e4353b8..dc0c41d 100644
--- a/src/modules/homeassistant/homeassistant.js
+++ b/src/modules/homeassistant/homeassistant.js
@@ -91,7 +91,7 @@ export class Homeassistant {
 
   callService(service, domain, entity_id = null, serviceData = null, callback = null) {
     let executeScriptCmd = new ExecuteScriptCommand(this.nextRequestId(), [
-      new ServiceAction(domain, service, entity_id ? [entity_id] : [], serviceData || {})
+      new ServiceAction(domain, service, entity_id ? [entity_id]: null, serviceData || {})
     ])
     this.sendCommand(executeScriptCmd, callback)
   }