TASK: Better animation when inspector group collapse

src/components/inspector-group/inspector-group.tsx

@@ -44,7 +44,11 @@ export class InspectorGroup {
 
   render() {
     return (<section role="group">
-      <neos-inspector-group-header icon={this.icon} label={this.label} open={this.isOpen}></neos-inspector-group-header>
+      <neos-inspector-group-header
+        icon={this.icon}
+        label={this.label}
+        open={this.isOpen}
+      ></neos-inspector-group-header>
       <div class={this.wrapperClassName()}>
         <div class="content">
           <slot/>

src/components/inspector-group/styles/inspector-group.dark.scss

@@ -7,12 +7,14 @@
   margin-top: -1px;
 
   .content-wrapper {
-    transition: max-height 600ms ease-in-out;
+    transition: max-height 400ms ease-in-out, opacity 500ms ease-in-out;
     max-height: 0;
+    opacity: 0;
 
     &--open {
       max-height: 1000px;
       height: auto;
+      opacity: 1;
     }
   }