Mac UE5: Window resize in shipping build freezes game

Hi, I am currently porting my UE 4.27 game to UE 5.2. I have most issues worked out, but I stumbled on something new when building a shipping version for Mac: when the game window is resized, when switching from fullscreen to windowed, or when the resolution is changed, the game freezes. The freeze can last for several seconds or even longer, effectively crashing the game.

Trying to isolate the problem, I have determined:

  • The problem only occurs on Mac
  • It only happens in Shipping builds, packaged development builds are fine
  • It happens in 5.2 (launcher and source builds) and 5.3, but not in 4.27
  • It happens on M1, M3, and Intel MacBooks
  • The severity depends on the complexity of the scene. If I have only a single static mesh, the freeze is not noticeable. But with just a few dozen simple meshes, it can already take several seconds.

I can easily reproduce the issue in a new project: an empty proudct is too simple to notice the delay, but a shipping build of the “Archvis” sample project takes more than five seconds to resize when pressing Option-Enter, even on an M3.

Does everyone run into the same problem, and is there a known workaround?

I have tried Fortnite and it doesn’t have the same problem. Fortnite should be on UE5.3, so it is possible to get a shipping build without the freezes on resolution changes. Maybe a configuration setting somewhere? The Metal version doesn’t seem to make a difference. Did no one else get this freeze on shipping builds?

Hi. Have you been able to solve the problem? I have the same issue when the window resize freezes the game :frowning: Maybe its something related to project/rendering settings?

Unfortunately no, I haven’t found a way to get rid of the freeze. I was forced to release updates with this as a known problem. I hope that future Unreal Engine versions will fix the problem, I haven’t tried 5.4 yet.

Has anyone found a solution to this? It does seem to lag even on the base third person map whenever you try resizing the window… Upgrading to 5.4.2 does half fix it on mouse and keyboard, but if you change the resolution via a gamepad it freezes the window again… I wouldn’t recommend upgrading though since it does mess with the textures you have, causing it to reset to albedo every time you open the editor.

So it looks like they did fix the bug but for UE version 5.1: Unreal Engine Issues and Bug Tracker (UE-180492). They’re also targeting the fix for 5.5, but they don’t mention any fix for the other versions yet.

For anyone else having this issue please bump up this post so versions 5.2 - 5.4 can be fixed as well!