diff --git a/internal/ui/ui_glfw.go b/internal/ui/ui_glfw.go
index 42489fdd2..742e2a3fa 100644
--- a/internal/ui/ui_glfw.go
+++ b/internal/ui/ui_glfw.go
@@ -1316,18 +1316,19 @@ func (u *UserInterface) updateVsync() {
 //
 // currentMonitor must be called on the main thread.
 func (u *UserInterface) currentMonitor() *glfw.Monitor {
-	if !u.isRunning() {
+	if u.window == nil {
 		return u.initMonitor
 	}
-	return currentMonitorImpl(u.window)
+	if m := monitorFromWindow(u.window); m != nil {
+		return m
+	}
+	return glfw.GetPrimaryMonitor()
 }
 
-// currentMonitorImpl returns the current active monitor.
+// monitorFromWindow returns the monitor from the given window.
 //
-// The given window might or might not be used to detect the monitor.
-//
-// currentMonitorImpl must be called on the main thread.
-func currentMonitorImpl(window *glfw.Window) *glfw.Monitor {
+// monitorFromWindow must be called on the main thread.
+func monitorFromWindow(window *glfw.Window) *glfw.Monitor {
 	// GetMonitor is available only in fullscreen.
 	if m := window.GetMonitor(); m != nil {
 		return m
@@ -1336,7 +1337,7 @@ func currentMonitorImpl(window *glfw.Window) *glfw.Monitor {
 	// Getting a monitor from a window position is not reliable in general (e.g., when a window is put across
 	// multiple monitors, or, before SetWindowPosition is called.).
 	// Get the monitor which the current window belongs to. This requires OS API.
-	if m := currentMonitorByOS(window); m != nil {
+	if m := monitorFromWindowByOS(window); m != nil {
 		return m
 	}
 
@@ -1344,7 +1345,8 @@ func currentMonitorImpl(window *glfw.Window) *glfw.Monitor {
 	if m := getMonitorFromPosition(window.GetPos()); m != nil {
 		return m.m
 	}
-	return glfw.GetPrimaryMonitor()
+
+	return nil
 }
 
 func (u *UserInterface) SetScreenTransparent(transparent bool) {
diff --git a/internal/ui/ui_glfw_darwin.go b/internal/ui/ui_glfw_darwin.go
index 097310ea3..c950c8ef5 100644
--- a/internal/ui/ui_glfw_darwin.go
+++ b/internal/ui/ui_glfw_darwin.go
@@ -183,11 +183,9 @@ func initialMonitorByOS() (*glfw.Monitor, error) {
 	return nil, nil
 }
 
-func currentMonitorByOS(w *glfw.Window) *glfw.Monitor {
+func monitorFromWindowByOS(w *glfw.Window) *glfw.Monitor {
 	var x, y C.int
-	// Note: [NSApp mainWindow] is nil when it doesn't have its border. Use w here.
-	win := w.GetCocoaWindow()
-	C.currentMonitorPos(C.uintptr_t(win), &x, &y)
+	C.currentMonitorPos(C.uintptr_t(w.GetCocoaWindow()), &x, &y)
 	for _, m := range ensureMonitors() {
 		if int(x) == m.x && int(y) == m.y {
 			return m.m
diff --git a/internal/ui/ui_glfw_unix.go b/internal/ui/ui_glfw_unix.go
index 00fee87b4..5d59adc72 100644
--- a/internal/ui/ui_glfw_unix.go
+++ b/internal/ui/ui_glfw_unix.go
@@ -159,7 +159,7 @@ func initialMonitorByOS() (*glfw.Monitor, error) {
 	return nil, nil
 }
 
-func currentMonitorByOS(_ *glfw.Window) *glfw.Monitor {
+func monitorFromWindowByOS(_ *glfw.Window) *glfw.Monitor {
 	// TODO: Implement this correctly. (#1119).
 	return nil
 }
diff --git a/internal/ui/ui_glfw_windows.go b/internal/ui/ui_glfw_windows.go
index e5beed0c4..d4b118415 100644
--- a/internal/ui/ui_glfw_windows.go
+++ b/internal/ui/ui_glfw_windows.go
@@ -69,7 +69,7 @@ func getSystemMetrics(nIndex int) (int32, error) {
 	return int32(r), nil
 }
 
-func monitorFromWindow(hwnd windows.HWND, dwFlags uint32) uintptr {
+func monitorFromWindow_(hwnd windows.HWND, dwFlags uint32) uintptr {
 	r, _, _ := procMonitorFromWindow.Call(uintptr(hwnd), uintptr(dwFlags))
 	return r
 }
@@ -150,7 +150,7 @@ func initialMonitorByOS() (*glfw.Monitor, error) {
 	return nil, nil
 }
 
-func currentMonitorByOS(w *glfw.Window) *glfw.Monitor {
+func monitorFromWindowByOS(w *glfw.Window) *glfw.Monitor {
 	return monitorFromWin32Window(windows.HWND(w.GetWin32Window()))
 }
 
@@ -158,7 +158,7 @@ func monitorFromWin32Window(w windows.HWND) *glfw.Monitor {
 	// Get the current monitor by the window handle instead of the window position. It is because the window
 	// position is not relaiable in some cases e.g. when the window is put across multiple monitors.
 
-	m := monitorFromWindow(w, monitorDefaultToNearest)
+	m := monitorFromWindow_(w, monitorDefaultToNearest)
 	if m == 0 {
 		// monitorFromWindow can return error on Wine. Ignore this.
 		return nil