diff --git a/caosdb-webui b/caosdb-webui
index b6677e848ed30cadeda5d1782bd4376ec6546031..7d67a76f1ceede440a2d4dad4db8dcbd0d61b9ed 160000
--- a/caosdb-webui
+++ b/caosdb-webui
@@ -1 +1 @@
-Subproject commit b6677e848ed30cadeda5d1782bd4376ec6546031
+Subproject commit 7d67a76f1ceede440a2d4dad4db8dcbd0d61b9ed
diff --git a/src/main/java/caosdb/datetime/UTCDateTime.java b/src/main/java/caosdb/datetime/UTCDateTime.java
index 846c8f9f266d4b834314b95e00973993d9031224..72a55faaa1d7822816a8ceab875e8ec8928f1529 100644
--- a/src/main/java/caosdb/datetime/UTCDateTime.java
+++ b/src/main/java/caosdb/datetime/UTCDateTime.java
@@ -162,6 +162,13 @@ public class UTCDateTime implements Interval {
     addLeapSecond(gc.getTimeInMillis() / 1000);
   }
 
+  /**
+   * Initialize the container with known leap seconds. This container has to be updated according to
+   * future changes of leap seconds.
+   *
+   * <p>Currently all leap seconds between 1972 and 2019 are registered here, with the most recent
+   * leap second being added for December 2016.
+   */
   private static void initLeapSeconds() {
 
     // june 1972