diff --git a/framework/core/ember/app/styles/bootstrap/variables.less b/framework/core/ember/app/styles/bootstrap/variables.less
index 8669a7cf8..2813aa0b6 100644
--- a/framework/core/ember/app/styles/bootstrap/variables.less
+++ b/framework/core/ember/app/styles/bootstrap/variables.less
@@ -16,4 +16,8 @@
 @input-border: @fl-body-control-bg;
 @input-border-focus: @fl-body-control-bg;
 @input-color: @fl-body-control-color;
-@input-color-placeholder: @fl-body-control-color;
\ No newline at end of file
+@input-color-placeholder: @fl-body-control-color;
+
+@zindex-composer: @zindex-navbar-fixed + 4;
+@zindex-pane: @zindex-navbar-fixed + 5;
+@zindex-alerts: @zindex-modal + 10;
diff --git a/framework/core/ember/app/styles/flarum/alerts.less b/framework/core/ember/app/styles/flarum/alerts.less
index 16b05c6fd..9268b7506 100644
--- a/framework/core/ember/app/styles/flarum/alerts.less
+++ b/framework/core/ember/app/styles/flarum/alerts.less
@@ -2,6 +2,7 @@
 	position: fixed;
 	bottom: 20px;
 	left: 20px;
+	z-index: @zindex-alerts;
 
 	& .alert {
 		display: inline-block;
diff --git a/framework/core/ember/app/styles/flarum/composer.less b/framework/core/ember/app/styles/flarum/composer.less
index 66a87fd96..21ac76025 100644
--- a/framework/core/ember/app/styles/flarum/composer.less
+++ b/framework/core/ember/app/styles/flarum/composer.less
@@ -6,7 +6,7 @@
 	bottom: 0;
 	left: 0;
 	right: 0;
-	z-index: @zindex-navbar-fixed + 2;
+	z-index: @zindex-composer;
 	pointer-events: none;
 	.transition(left 0.2s);
 
diff --git a/framework/core/ember/app/styles/flarum/index.less b/framework/core/ember/app/styles/flarum/index.less
index 61c2662fe..05f25d232 100644
--- a/framework/core/ember/app/styles/flarum/index.less
+++ b/framework/core/ember/app/styles/flarum/index.less
@@ -98,7 +98,7 @@
 
 	&.paned {
 		position: fixed;
-		z-index: @zindex-navbar-fixed + 1;
+		z-index: @zindex-pane;
 		overflow: auto;
 		top: 56px;
 		bottom: 0;
@@ -111,6 +111,10 @@
 		&.showing, .with-pane & {
 			left: 0;
 		}
+		.with-pane & {
+			z-index: @zindex-composer - 1;
+			.transition(none);
+		}
 		& .container {
 			width: auto;
 			margin: 0;
@@ -247,4 +251,4 @@
 .load-more {
 	text-align: center;
 	margin-top: 10px;
-}
\ No newline at end of file
+}
diff --git a/framework/core/ember/app/styles/flarum/layout.less b/framework/core/ember/app/styles/flarum/layout.less
index 911722059..ca2d35a82 100644
--- a/framework/core/ember/app/styles/flarum/layout.less
+++ b/framework/core/ember/app/styles/flarum/layout.less
@@ -64,7 +64,7 @@ body {
 	margin-right: 25px;
 
 	& .back {
-		z-index: 3; // z-index of an active .btn-group .btn is 2
+		z-index: 3 !important; // z-index of an active .btn-group .btn is 2
 		border-radius: @border-radius-base !important;
 		.transition(border-radius 0.2s);
 	}