Improve composer visiblity (#8578)

Co-authored-by: Michael Telatynski <7t3chguy@gmail.com>

res/css/structures/_RoomView.scss

@@ -32,6 +32,12 @@ limitations under the License.
     position: relative;
 }
 
+.mx_MainSplit_timeline {
+    .mx_MessageComposer_wrapper {
+        margin: $spacing-8 $spacing-16;
+    }
+}
+
 .mx_RoomView_auxPanel {
     min-width: 0px;
     width: 100%;
@@ -155,7 +161,7 @@ limitations under the License.
     .mx_RoomView_messageListWrapper {
         justify-content: flex-start;
 
-        >.mx_RoomView_MessageList > li > ol {
+        > .mx_RoomView_MessageList > li > ol {
             list-style-type: none;
         }
     }