diff --git a/docs/changelog.rst b/docs/changelog.rst
index dcd7ba0ac..809864e4b 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -17,6 +17,9 @@ Changelog
   fullscreen/maximized/minimized. This replaces the ``--start-in-fullscreen``
   flag introduced in the previous release (:iss:`935`)
 
+- Fix drag-scrolling not working when the mouse leaves the window confines
+  (:iss:`917`)
+
 - Linux: Ensure that the python embedded in the kitty binary build uses
   UTF-8 mode to process command-line arguments (:iss:`924`)
 
diff --git a/kitty/data-types.h b/kitty/data-types.h
index 8b9a6c2e0..915f2d23e 100644
--- a/kitty/data-types.h
+++ b/kitty/data-types.h
@@ -281,7 +281,7 @@ void colorprofile_pop_dynamic_colors(ColorProfile*);
 
 void set_mouse_cursor(MouseShape);
 void enter_event();
-void mouse_event(int, int);
+void mouse_event(int, int, int);
 void focus_in_event();
 void wakeup_io_loop(bool);
 void scroll_event(double, double, int);
diff --git a/kitty/glfw.c b/kitty/glfw.c
index 7ed7156ef..e24fef8b2 100644
--- a/kitty/glfw.c
+++ b/kitty/glfw.c
@@ -157,9 +157,9 @@ mouse_button_callback(GLFWwindow *w, int button, int action, int mods) {
     show_mouse_cursor(w);
     double now = monotonic();
     global_state.callback_os_window->last_mouse_activity_at = now;
-    if (button >= 0 && (unsigned int)button < sizeof(global_state.callback_os_window->mouse_button_pressed)/sizeof(global_state.callback_os_window->mouse_button_pressed[0])) {
+    if (button >= 0 && (unsigned int)button < arraysz(global_state.callback_os_window->mouse_button_pressed)) {
         global_state.callback_os_window->mouse_button_pressed[button] = action == GLFW_PRESS ? true : false;
-        if (is_window_ready_for_callbacks()) mouse_event(button, mods);
+        if (is_window_ready_for_callbacks()) mouse_event(button, mods, action);
     }
     global_state.callback_os_window = NULL;
 }
@@ -173,7 +173,7 @@ cursor_pos_callback(GLFWwindow *w, double x, double y) {
     global_state.callback_os_window->cursor_blink_zero_time = now;
     global_state.callback_os_window->mouse_x = x * global_state.callback_os_window->viewport_x_ratio;
     global_state.callback_os_window->mouse_y = y * global_state.callback_os_window->viewport_y_ratio;
-    if (is_window_ready_for_callbacks()) mouse_event(-1, 0);
+    if (is_window_ready_for_callbacks()) mouse_event(-1, 0, -1);
     global_state.callback_os_window = NULL;
 }
 
diff --git a/kitty/mouse.c b/kitty/mouse.c
index 40ee24c90..078cbfb16 100644
--- a/kitty/mouse.c
+++ b/kitty/mouse.c
@@ -179,10 +179,7 @@ update_drag(bool from_button, Window *w, bool is_release, int modifiers) {
 bool
 drag_scroll(Window *w, OSWindow *frame) {
     unsigned int margin = frame->fonts_data->cell_height / 2;
-    double left = window_left(w, frame), top = window_top(w, frame), right = window_right(w, frame), bottom = window_bottom(w, frame);
-    double x = frame->mouse_x, y = frame->mouse_y;
-    if (y < top || y > bottom) return false;
-    if (x < left || x > right) return false;
+    double y = frame->mouse_y;
     bool upwards = y <= (w->geometry.top + margin);
     if (upwards || y >= w->geometry.bottom - margin) {
         Screen *screen = w->render_data.screen;
@@ -488,23 +485,30 @@ enter_event() {
 }
 
 void
-mouse_event(int button, int modifiers) {
+mouse_event(int button, int modifiers, int action) {
     MouseShape old_cursor = mouse_cursor_shape;
     bool in_tab_bar;
     unsigned int window_idx = 0;
     Window *w = NULL;
-    if (button == -1 && global_state.active_drag_in_window) {  // drag move
-        w = window_for_id(global_state.active_drag_in_window);
-        if (w) {
-            button = currently_pressed_button();
-            if (button == GLFW_MOUSE_BUTTON_LEFT) {
-                clamp_to_window = true;
-                handle_move_event(w, button, modifiers, window_idx);
-                clamp_to_window = false;
-                return;
+    if (global_state.active_drag_in_window) {
+        if (button == -1) {  // drag move
+            w = window_for_id(global_state.active_drag_in_window);
+            if (w) {
+                button = currently_pressed_button();
+                if (button == GLFW_MOUSE_BUTTON_LEFT) {
+                    clamp_to_window = true;
+                    handle_move_event(w, button, modifiers, window_idx);
+                    clamp_to_window = false;
+                    return;
+                }
+            }
+        }
+        else if (action == GLFW_RELEASE && button == GLFW_MOUSE_BUTTON_LEFT) {
+            w = window_for_id(global_state.active_drag_in_window);
+            if (w) {
+                update_drag(true, w, true, modifiers);
             }
         }
-
     }
     w = window_for_event(&window_idx, &in_tab_bar);
     if (in_tab_bar) {