diff --git a/lib/public/Activity/IEvent.php b/lib/public/Activity/IEvent.php
index eba426c5ecffb..6014b75123c75 100644
--- a/lib/public/Activity/IEvent.php
+++ b/lib/public/Activity/IEvent.php
@@ -310,6 +310,10 @@ public function getObjectName(): string;
 	public function getLink(): string;
 
 	/**
+	 * Set the absolute url for the icon (should be colored black or not have a color)
+	 *
+	 * It's automatically color inverted by clients when needed
+	 *
 	 * @param string $icon
 	 * @return $this
 	 * @throws InvalidValueException if the icon is invalid
@@ -319,6 +323,10 @@ public function getLink(): string;
 	public function setIcon(string $icon): self;
 
 	/**
+	 * Get the absolute url for the icon (should be colored black or not have a color)
+	 *
+	 * It's automatically color inverted by clients when needed
+	 *
 	 * @return string
 	 * @since 11.0.0
 	 */
diff --git a/lib/public/Notification/INotification.php b/lib/public/Notification/INotification.php
index 6083cca4f9a85..7a1ee960b2803 100644
--- a/lib/public/Notification/INotification.php
+++ b/lib/public/Notification/INotification.php
@@ -249,6 +249,10 @@ public function setLink(string $link): INotification;
 	public function getLink(): string;
 
 	/**
+	 * Set the absolute url for the icon (should be colored black or not have a color)
+	 *
+	 * It's automatically color inverted by clients when needed
+	 *
 	 * @param string $icon
 	 * @return $this
 	 * @throws InvalidValueException if the icon is invalid
@@ -258,6 +262,10 @@ public function getLink(): string;
 	public function setIcon(string $icon): INotification;
 
 	/**
+	 * Get the absolute url for the icon (should be colored black or not have a color)
+	 *
+	 * It's automatically color inverted by clients when needed
+	 *
 	 * @return string
 	 * @since 11.0.0
 	 */