FIxed scrolling issue on drafts (#28187)

webapp/channels/src/components/drafts/drafts.scss

@@ -13,8 +13,10 @@
     }
 
     &__main {
+        position: absolute;
         display: flex;
         overflow: auto;
+        height: 100%;
         flex-flow: column nowrap;
         padding: 24px;
         grid-area: list;