diff --git a/src/js/mujs/window.c b/src/js/mujs/window.c
index 0010375b8..d661cddb4 100644
--- a/src/js/mujs/window.c
+++ b/src/js/mujs/window.c
@@ -56,6 +56,7 @@
 #include "viewer/text/draw.h"
 #include "viewer/text/form.h"
 #include "viewer/text/link.h"
+#include "viewer/text/view.h"
 #include "viewer/text/vs.h"
 
 struct listener {
@@ -530,6 +531,23 @@ end:
 	js_pushboolean(J, ret);
 }
 
+static void
+mjs_window_scrollByLines(js_State *J)
+{
+#ifdef ECMASCRIPT_DEBUG
+	fprintf(stderr, "%s:%s\n", __FILE__, __FUNCTION__);
+#endif
+	struct ecmascript_interpreter *interpreter = (struct ecmascript_interpreter *)js_getcontext(J);
+	struct view_state *vs = interpreter->vs;
+	struct document_view *doc_view = vs->doc_view;
+	struct session *ses = doc_view->session;
+	int steps = js_toint32(J, 1);
+
+	vertical_scroll(ses, doc_view, steps);
+
+	js_pushundefined(J);
+}
+
 static void
 mjs_window_setInterval(js_State *J)
 {
@@ -829,6 +847,7 @@ mjs_window_init(js_State *J)
 		addmethod(J, "window.open", mjs_window_open, 3);
 		addmethod(J, "window.postMessage", mjs_window_postMessage, 3);
 		addmethod(J, "window.removeEventListener", mjs_window_removeEventListener, 3);
+		addmethod(J, "window.scrollByLines", mjs_window_scrollByLines, 1);
 		addmethod(J, "window.setInterval", mjs_window_setInterval, 2);
 		addmethod(J, "window.setTimeout", mjs_window_setTimeout, 2);
 		addmethod(J, "window.toString", mjs_window_toString, 0);
@@ -878,6 +897,7 @@ mjs_push_window(js_State *J, struct view_state *vs)
 		addmethod(J, "window.open", mjs_window_open, 3);
 		addmethod(J, "window.postMessage", mjs_window_postMessage, 3);
 		addmethod(J, "window.removeEventListener", mjs_window_removeEventListener, 3);
+		addmethod(J, "window.scrollByLines", mjs_window_scrollByLines, 1);
 		addmethod(J, "window.setInterval", mjs_window_setInterval, 2);
 		addmethod(J, "window.setTimeout", mjs_window_setTimeout, 2);
 		addmethod(J, "window.toString", mjs_window_toString, 0);