diff --git a/docs/changelog.rst b/docs/changelog.rst
index 5ad23f935..0eebd16a9 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -72,6 +72,8 @@ Detailed list of changes
 
 - Splits layout: Fix :ac:`move_window_forward` not working (:iss:`7264`)
 
+- macOS: Fix an abort due to an assertion when a program tries to set an invalid window title (:iss:`7271`)
+
 0.33.1 [2024-03-21]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
diff --git a/glfw/cocoa_window.m b/glfw/cocoa_window.m
index de1b641a7..79a274764 100644
--- a/glfw/cocoa_window.m
+++ b/glfw/cocoa_window.m
@@ -1963,9 +1963,11 @@ void _glfwPlatformDestroyWindow(_GLFWwindow* window)
     window->ns.object = nil;
 }
 
-void _glfwPlatformSetWindowTitle(_GLFWwindow* window UNUSED, const char* title)
+void _glfwPlatformSetWindowTitle(_GLFWwindow* window, const char* title)
 {
+    if (!title) return;
     NSString* string = @(title);
+    if (!string) return;  // the runtime failed to convert title to an NSString
     [window->ns.object setTitle:string];
     // HACK: Set the miniwindow title explicitly as setTitle: doesn't update it
     //       if the window lacks NSWindowStyleMaskTitled
diff --git a/kitty/cocoa_window.m b/kitty/cocoa_window.m
index f70d7defc..b89fca4e8 100644
--- a/kitty/cocoa_window.m
+++ b/kitty/cocoa_window.m
@@ -748,12 +748,14 @@ cocoa_create_global_menu(void) {
 
 void
 cocoa_update_menu_bar_title(PyObject *pytitle) {
+    if (!pytitle) return;
     NSString *title = nil;
     if (OPT(macos_menubar_title_max_length) > 0 && PyUnicode_GetLength(pytitle) > OPT(macos_menubar_title_max_length)) {
         static char fmt[64];
         snprintf(fmt, sizeof(fmt), "%%%ld.%ldU%%s", OPT(macos_menubar_title_max_length), OPT(macos_menubar_title_max_length));
         RAII_PyObject(st, PyUnicode_FromFormat(fmt, pytitle, "…"));
         if (st) title = @(PyUnicode_AsUTF8(st));
+        else PyErr_Print();
     } else {
         title = @(PyUnicode_AsUTF8(pytitle));
     }
diff --git a/kitty/glfw.c b/kitty/glfw.c
index da6d1ae34..1f73c3a9f 100644
--- a/kitty/glfw.c
+++ b/kitty/glfw.c
@@ -98,7 +98,8 @@ update_menu_bar_title(PyObject *title UNUSED) {
     static char buf[2048];
     strip_csi_(PyUnicode_AsUTF8(title), buf, arraysz(buf));
     RAII_PyObject(stitle, PyUnicode_FromString(buf));
-    cocoa_update_menu_bar_title(stitle);
+    if (stitle) cocoa_update_menu_bar_title(stitle);
+    else PyErr_Print();
 #endif
 }