diff --git a/panels/history/ha-panel-history.html b/panels/history/ha-panel-history.html
index ac911f6185..60e800dccd 100644
--- a/panels/history/ha-panel-history.html
+++ b/panels/history/ha-panel-history.html
@@ -132,6 +132,8 @@ Polymer({
 
   attached: function () {
     this.datePicker = new window.Pikaday({
+      // Bind field to dummy input to prevent pikaday from overwriting
+      // field value with its internal formatting.
       field: document.createElement('input'),
       trigger: this.$.datePicker.inputElement,
       onSelect: this.hass.entityHistoryActions.changeCurrentDate,
diff --git a/panels/logbook/ha-panel-logbook.html b/panels/logbook/ha-panel-logbook.html
index 629a05e4ea..f3a8279c5b 100644
--- a/panels/logbook/ha-panel-logbook.html
+++ b/panels/logbook/ha-panel-logbook.html
@@ -139,6 +139,8 @@ Polymer({
 
   attached: function () {
     this.datePicker = new window.Pikaday({
+      // Bind field to dummy input to prevent pikaday from overwriting
+      // field value with its internal formatting.
       field: document.createElement('input'),
       trigger: this.$.datePicker.inputElement,
       onSelect: this.hass.logbookActions.changeCurrentDate,