diff --git a/src/main/resources/images/collapse.png b/src/main/resources/images/collapse.png new file mode 100644 index 0000000000..531d915eec Binary files /dev/null and b/src/main/resources/images/collapse.png differ diff --git a/src/main/resources/images/expand.png b/src/main/resources/images/expand.png new file mode 100644 index 0000000000..e54a8337c4 Binary files /dev/null and b/src/main/resources/images/expand.png differ