diff --git a/ui/layers/generic_box.cpp b/ui/layers/generic_box.cpp
index bbf7109..bfcc7aa 100644
--- a/ui/layers/generic_box.cpp
+++ b/ui/layers/generic_box.cpp
@@ -62,6 +62,10 @@ void GenericBox::prepare() {
 			pinnedToBottom->move(0, outer - height);
 		}, pinnedToBottom->lifetime());
 	}
+
+	if (const auto onstack = _initScroll) {
+		onstack();
+	}
 }
 
 void GenericBox::addSkip(int height) {
diff --git a/ui/layers/generic_box.h b/ui/layers/generic_box.h
index 4c3baae..53be668 100644
--- a/ui/layers/generic_box.h
+++ b/ui/layers/generic_box.h
@@ -38,6 +38,9 @@ public:
 	void setFocusCallback(Fn<void()> callback) {
 		_focus = callback;
 	}
+	void setInitScrollCallback(Fn<void()> callback) {
+		_initScroll = callback;
+	}
 	void setShowFinishedCallback(Fn<void()> callback) {
 		_showFinished = callback;
 	}
@@ -136,6 +139,7 @@ private:
 
 	FnMut<void(not_null<GenericBox*>)> _init;
 	Fn<void()> _focus;
+	Fn<void()> _initScroll;
 	Fn<void()> _showFinished;
 	rpl::event_stream<> _showFinishes;
 	object_ptr<Ui::VerticalLayout> _owned;