diff --git a/docs/changelog.rst b/docs/changelog.rst
index 7e293edcd..ce34f1bd3 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -190,6 +190,8 @@ Detailed list of changes
 
 - Wayland: fix using remote control to resize OS windows on some tiling compositors leading to broken rendering
 
+- macOS: fix ``edge=none`` panel height shrinking when ``margin_top`` is non-zero in the panel/quick-access-terminal kittens (:iss:`10278`)
+
 
 0.48.0 [2026-07-18]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/glfw/cocoa_window.m b/glfw/cocoa_window.m
index 86cd79f87..c48a13a4d 100644
--- a/glfw/cocoa_window.m
+++ b/glfw/cocoa_window.m
@@ -2799,7 +2799,11 @@ _glfwPlatformSetLayerShellConfig(_GLFWwindow* window, const GLFWLayerShellConfig
         if (height < 1.) height = NSHeight(placement_frame);
     }
 
-    if (config.edge != GLFW_EDGE_CENTER_SIZED) {
+    if (config.edge == GLFW_EDGE_NONE) {
+        // For edge=none the panel has a fixed size; margins only translate its position
+        x += config.requested_left_margin;
+        y -= config.requested_top_margin;
+    } else if (config.edge != GLFW_EDGE_CENTER_SIZED) {
         x += config.requested_left_margin; width -= config.requested_left_margin + config.requested_right_margin;
         y += config.requested_bottom_margin; height -= config.requested_top_margin + config.requested_bottom_margin;
     }