add wrapper we can then add padding to when sticking headers

res/css/structures/_LeftPanel2.scss

@@ -121,6 +121,14 @@ $tagPanelWidth: 70px; // only applies in this file, used for calculations
             }
         }
 
+        .mx_LeftPanel2_roomListWrapper {
+            display: flex;
+            flex-grow: 1;
+            overflow: hidden;
+            min-height: 0;
+
+        }
+
         .mx_LeftPanel2_actualRoomListContainer {
             flex-grow: 1; // fill the available space
             overflow-y: auto;

src/components/structures/LeftPanel2.tsx

@@ -325,6 +325,7 @@ export default class LeftPanel2 extends React.Component<IProps, IState> {
                 <aside className="mx_LeftPanel2_roomListContainer">
                     {this.renderHeader()}
                     {this.renderSearchExplore()}
+                    <div className="mx_LeftPanel2_roomListWrapper">
                         <div
                             className={roomListClasses}
                             onScroll={this.onScroll}
@@ -335,6 +336,7 @@ export default class LeftPanel2 extends React.Component<IProps, IState> {
                         >
                             {roomList}
                         </div>
+                    </div>
                 </aside>
             </div>
         );