MC-3392: Hide Content block/ container from the stage

- Fix tabs broken by improvements from mainline

Author: davemacaulay

app/code/Magento/PageBuilder/view/adminhtml/web/js/content-type/tabs/preview.js

@@ -108,6 +108,16 @@ export default class Preview extends PreviewCollection {
                 this.updateData("default_active", newDefaultActiveTab);
             }
         });
+
+        // Monitor focus tab to start / stop interaction on the stage, debounce to avoid duplicate calls
+        this.focusedTab.subscribe(_.debounce((index: number) => {
+            if (index !== null) {
+                events.trigger("stage:interactionStart");
+            } else {
+                // We have to force the stop as the event firing is inconsistent for certain operations
+                events.trigger("stage:interactionStop", {force : true});
+            }
+        }, 1));
     }
 
     /**

app/code/Magento/PageBuilder/view/adminhtml/web/js/stage.js

@@ -181,8 +181,8 @@ export default class Stage {
             ++interactionLevel;
             this.interacting(true);
         });
-        events.on("stage:interactionStop", () => {
-            if (--interactionLevel === 0) {
+        events.on("stage:interactionStop", (args: {force: boolean}) => {
+            if (--interactionLevel === 0 || (_.isObject(args) && args.force === true)) {
                 this.interacting(false);
             }
         });