diff --git a/backends/imgui_impl_osx.mm b/backends/imgui_impl_osx.mm
index 189dd53e6..4d3c5dcf0 100644
--- a/backends/imgui_impl_osx.mm
+++ b/backends/imgui_impl_osx.mm
@@ -403,8 +403,33 @@ IMGUI_IMPL_API void ImGui_ImplOSX_NewFrame(void* _Nullable view) {
 #endif
 
 
+
+NSLock *ImGui_IO_lock;
+
+
+@interface ScopedLock : NSObject
+@property (strong) NSLock *lockptr;
+@end
+
+@implementation ScopedLock
+
+- (id)init:(NSLock *)incoming
+{
+    _lockptr = incoming;
+    [_lockptr lock];
+    return self;
+}
+
+- (void)dealloc {
+    [_lockptr unlock];
+}
+@end
+
+
 bool ImGui_ImplOSX_Init(NSView* view)
 {
+    ImGui_IO_lock = [[NSLock alloc] init];
+
     ImGuiIO& io = ImGui::GetIO();
     ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
     IMGUI_CHECKVERSION();
@@ -629,8 +654,18 @@ void ImGui_ImplOSX_NewFrame(NSView* view)
     // Setup display size
     if (view)
     {
-        const float dpi = (float)[view.window backingScaleFactor];
-        io.DisplaySize = ImVec2((float)view.bounds.size.width, (float)view.bounds.size.height);
+        dispatch_async(dispatch_get_main_queue(), ^{
+            [bd->exclusive.lock lock];
+            bd->exclusive.backingScaleFactor = view.window.backingScaleFactor;
+            bd->exclusive.bounds = view.bounds;
+            [bd->exclusive.lock unlock];
+        });
+
+        [bd->exclusive.lock lock];
+        const float dpi = (float) bd->exclusive.backingScaleFactor;
+        io.DisplaySize = ImVec2((float) bd->exclusive.bounds.size.width, bd->exclusive.bounds.size.height);
+        [bd->exclusive.lock unlock];
+
         io.DisplayFramebufferScale = ImVec2(dpi, dpi);
     }
 
@@ -674,6 +709,8 @@ static bool ImGui_ImplOSX_HandleEvent(NSEvent* event, NSView* view)
         return false;
     ImGuiIO& io = ImGui::GetIO();
 
+    ScopedLock *sclock = [[ScopedLock alloc] init:ImGui_IO_lock];
+
     if (event.type == NSEventTypeLeftMouseDown || event.type == NSEventTypeRightMouseDown || event.type == NSEventTypeOtherMouseDown)
     {
         int button = (int)[event buttonNumber];