use a common variable on the block model for isOpen, to be able to make Actions show when open.

src/Umbraco.Web.UI.Client/src/views/blockelements/inlineblock/inlineblock.editor.controller.js

@@ -1,16 +1,12 @@
 (function () {
     'use strict';
 
-    function InlineBlockEditor($scope) {
+    function InlineBlockEditor() {
 
         const bc = this;
 
-        bc.isOpen = false;
-        bc.caretIconType = "icon-navigation-right";
-
-        bc.openBlock = function() {
-            bc.isOpen = !bc.isOpen;
-            bc.caretIconType = bc.isOpen ? "icon-navigation-down" : "icon-navigation-right";
+        bc.openBlock = function(block) {
+            block.isOpen = !block.isOpen;
         }
 
     }

src/Umbraco.Web.UI.Client/src/views/blockelements/inlineblock/inlineblock.editor.html

@@ -1,10 +1,10 @@
-<div class="blockelement-inlineblock-editor" ng-class="{'--open': bc.isOpen}" ng-controller="Umbraco.PropertyEditors.BlockEditor.InlineBlockEditor as bc">
+<div class="blockelement-inlineblock-editor" ng-controller="Umbraco.PropertyEditors.BlockEditor.InlineBlockEditor as bc">
     <button type="button" class="btn-reset umb-outline blockelement__draggable-element" ng-click="bc.openBlock(block)" focus-when="{{vm.moveFocusToBlock === block}}">
         <span class="caret"></span>
         <i class="icon {{block.content.icon}}"></i>
         <span>{{block.label}}</span>
     </button>
-    <div class="blockelement-inlineblock-editor__inner" ng-if="bc.isOpen === true">
+    <div class="blockelement-inlineblock-editor__inner" ng-if="block.isOpen === true">
         <umb-element-editor-content model="block.content"></umb-element-editor-content>
     </div>
 </div>

src/Umbraco.Web.UI.Client/src/views/blockelements/inlineblock/inlineblock.editor.less

@@ -6,7 +6,7 @@
     border-radius: @baseBorderRadius;
     transition: border-color 120ms;
 
-    &:not(.--open):hover {
+    .umb-block-list__block:not(.--open) &:hover {
         border-color: @gray-8;
     }
 
@@ -43,7 +43,7 @@
         }
     }
 
-    &.--open {
+    .umb-block-list__block.--open & {
         border-color: @gray-8;
         box-shadow: 0 0 2px 0px rgba(0, 0, 0, 0.05);
         > button {
@@ -55,7 +55,7 @@
 }
 .blockelement-inlineblock-editor__inner {
     border-top: 1px solid @gray-8;
-    background-color: @gray-11;
+    background-color: @gray-12;
     
     .umb-group-panel {
         background-color: transparent;

src/Umbraco.Web.UI.Client/src/views/propertyeditors/blocklist/blocklist.component.html

@@ -14,7 +14,7 @@
                 >
                 </button>
 
-                <div class="umb-block-list__block">
+                <div class="umb-block-list__block" ng-class="{'--open':block.isOpen}">
                     <div class="umb-block-list__block--content" ng-if="block.view" ng-include="block.view">
                     </div>
 

src/Umbraco.Web.UI.Client/src/views/propertyeditors/blocklist/blocklist.component.less

@@ -21,7 +21,10 @@
         transition: opacity 120ms;
     }
 
-    &:hover, &:focus, &:focus-within {
+    &:hover,
+    &:focus,
+    &:focus-within,
+    &.--open {
         
         > .umb-block-list__block--actions {
             opacity: 1;