diff --git a/admin/javascript/LeftAndMain.Layout.js b/admin/javascript/LeftAndMain.Layout.js
index a4b8c261c..b35bd4199 100644
--- a/admin/javascript/LeftAndMain.Layout.js
+++ b/admin/javascript/LeftAndMain.Layout.js
@@ -104,9 +104,21 @@
 				}
 			}
 
+			// Calculate what columns are already hidden pre-layout
+			var prehidden = {
+				content: spec.content.hasClass('column-hidden'),
+				preview: spec.preview.hasClass('column-hidden')
+			};
+
+			// Calculate what columns will be hidden (zero width) post-layout
+			var posthidden = {
+				content: contentWidth === 0,
+				preview: previewWidth === 0
+			};
+
 			// Apply classes for elements that might not be visible at all.
-			spec.content.toggleClass('column-hidden', contentWidth===0);
-			spec.preview.toggleClass('column-hidden', previewWidth===0);
+			spec.content.toggleClass('column-hidden', posthidden.content);
+			spec.preview.toggleClass('column-hidden', posthidden.preview);
 
 			// Apply the widths to columns, and call subordinate layouts to arrange the children.
 			menu.bounds({'x': left, 'y': top, 'height': bottom - top, 'width': menuWidth});
@@ -115,12 +127,15 @@
 			left += menuWidth;
 
 			content.bounds({'x': left, 'y': top, 'height': bottom - top, 'width': contentWidth});
-			content.doLayout();
+			if (!posthidden.content) content.doLayout();
 
 			left += contentWidth;
 
 			preview.bounds({'x': left, 'y': top, 'height': bottom - top, 'width': previewWidth});
-			preview.doLayout();
+			if (!posthidden.preview) preview.doLayout();
+
+			if (posthidden.content !== prehidden.content) spec.content.trigger('columnvisibilitychanged');
+			if (posthidden.preview !== prehidden.preview) spec.preview.trigger('columnvisibilitychanged');
 
 			return container;
 		};
diff --git a/admin/javascript/LeftAndMain.Preview.js b/admin/javascript/LeftAndMain.Preview.js
index a607e0474..7856e9da5 100644
--- a/admin/javascript/LeftAndMain.Preview.js
+++ b/admin/javascript/LeftAndMain.Preview.js
@@ -198,6 +198,7 @@
 			 * Caveat: the preview will be automatically enabled when ".cms-previewable" class is detected.
 			 */
 			disablePreview: function() {
+				this.setPendingURL(null);
 				this._loadUrl('about:blank');
 				this._block();
 				this.changeMode('content', false);
@@ -304,6 +305,18 @@
 				}
 			},
 
+			/** @var string A URL that should be displayed in this preview panel once it becomes visible */
+			PendingURL: null,
+
+			oncolumnvisibilitychanged: function() {
+				var url = this.getPendingURL();
+				if (url && !this.is('.column-hidden')) {
+					this.setPendingURL(null);
+					this._loadUrl(url);
+					this._unblock();
+				}
+			},
+
 			/**
 			 * Update preview whenever a form is submitted.
 			 * This is an alternative to the LeftAndmMain::loadPanel functionality which we already
@@ -369,20 +382,37 @@
 					});
 				}
 
+				var url = null;
+
 				if (currentState[0]) {
 					// State is available on the newly loaded content. Get it.
-					this._loadUrl(currentState[0].url);
-					this._unblock();
+					url = currentState[0].url;
 				} else if (states.length) {
 					// Fall back to the first available content state.
 					this.setCurrentStateName(states[0].name);
-					this._loadUrl(states[0].url);
-					this._unblock();
+					url = states[0].url;
 				} else {
 					// No state available at all.
 					this.setCurrentStateName(null);
+				}
+
+				// If this preview panel isn't visible at the moment, delay loading the URL until it (maybe) is later
+				if (this.is('.column-hidden')) {
+					this.setPendingURL(url);
+					this._loadUrl('about:blank');
 					this._block();
 				}
+				else {
+					this.setPendingURL(null);
+
+					if (url) {
+						this._loadUrl(url);
+						this._unblock();
+					}
+					else {
+						this._block();
+					}
+				}
 
 				return this;
 			},