[Sonoma] macOS app windows becomes randomly blurry multiple times during the day

[frnak]

Hi everyone, I’ve recently been seeing a very odd behaviour on Sonoma...


I'm currently using 2x 1440p monitors connected to a Mac Studio, and on almost a daily basis after using Mission Control, the app windows on my screen will become ever so slightly blurry and slightly offset from their original position. It's very subtle, like a slight blur filter has been added to each app window.

The only way to get out of this state is to drag the window from their position. This somehow resets their rendering, and makes them sharp again. This behaviour is extremely annoying, as it happens multiple times on a daily basis at completely random intervals.

Here's a screenshot (zoomed in) I took where you can see the difference when it's blurry vs the regular state (after dragging the window). The captured screenshot even shows the blurriness, so it's not an issue with the monitor.

This issue has persisted for many months now, and searching online doesn't seem to yield any answers, as it's very subtle (but noticeable). I’m aware of the way Mac does display scaling poorly, which could be the culprit here. But I also have a M2 MacBook Pro 16” that I use with these two monitor, which I have never seen this issue occur. Which begs the question…is this a MacOS issue, or is it a Mac Studio issue?

 

[Fishrrman]

Just GUESSES on my part.

Looks to be a "synching" issue between the displays and the Studio's GPU.

Do you use the same connection scheme on the MBP as you do on the Studio?
By that, I mean (for example), do you use an HDMI-to-HDMI connection on both?

I'm wondering if it could be "a cable problem".
Do you use the same CABLE for both Macs?

 

[galad]

Do you use the "Show Desktop" Exposé feature? Probably it fails to put the windows back properly.

 

[frnak]

Just GUESSES on my part.

Looks to be a "synching" issue between the displays and the Studio's GPU.

Do you use the same connection scheme on the MBP as you do on the Studio?
By that, I mean (for example), do you use an HDMI-to-HDMI connection on both?

I'm wondering if it could be "a cable problem".
Do you use the same CABLE for both Macs?

I've tried the same cables and different cables and across different types (thunderbolt to HDMI, HDMI to HDMI), all result in similar issues on the Studio. It could just be coincidence that I haven't seen it happen on the MBP, as I definitely use the Studio more than the Pro. Then again, since it doesn't happen all the time, sometimes triggering it takes a while (and unpredictable).

 

[frnak]

Do you use the "Show Desktop" Exposé feature? Probably it fails to put the windows back properly.

I do, the blurring of the windows and the offsets happen in two different instances. It seems like when I restore windows from "Show Desktop", or from Mission Control, all of the windows are blurred all at once. But the slight offset only happens when I click window from Mission Control to bring it back into focus.


It almost feels like there's a bug somewhere in Sonoma when the windows are resized for Mission Control (scaling down all of the windows so it fit on the screen for you to click on), that rendering of the windows is not re-rendered after mission control is dismissed, causing the app windows to be "stuck" in low resolution...just a hypothesis.

Still doesn't explain why the MBP exhibits this a lot less though...