left_sidebar: Correct filter-input ellipsis bug in Safari.

web/styles/left_sidebar.css

@@ -1082,6 +1082,13 @@ li.top_left_scheduled_messages {
         .input {
             white-space: nowrap;
             overflow: hidden;
+        }
+
+        /* We only establish the ellipsis when
+           the input is not focused, thanks to a
+           Safari bug that makes long inputs
+           unreachable and unscrollable. */
+        .input:not(:focus) {
             text-overflow: ellipsis;
         }
     }