This doesn't work with multiple monitors

[tzarger]

Is there was a way to get this to display on all monitors. Using Thunderbolt 4K External Monitors.

[monroewilliams]

It should work with multiple monitors just fine (I use it on machines with 3 and 4 monitors myself).

Apple did break multiple monitor support for it at some point on macOS 13.3 (see #11 ), and they fixed that issue with the release of macOS 13.5. If you're on a version between those two, you might try updating to 13.5 and see if the problem resolves.

Unfortunately, they also seem to have broken something in a different way on macOS 14 Sonoma (see the other currently open issues for details). I haven't had a chance to chase down the current issues with Sonoma yet.

[tzarger]

It should work with multiple monitors just fine (I use it on machines with 3 and 4 monitors myself).

Apple did break multiple monitor support for it at some point on macOS 13.3 (see #11 ), and they fixed that issue with the release of macOS 13.5. If you're on a version between those two, you might try updating to 13.5 and see if the problem resolves.

Unfortunately, they also seem to have broken something in a different way on macOS 14 Sonoma (see the other currently open issues for details). I haven't had a chance to chase down the current issues with Sonoma yet.

Hello, yes I am on Sonoma 14.0. Thanks for your response. I'll keep an eye out to see if have a chance to track down the issue with Sonoma. Thank you again.

[StitchDave]

Second vote to get this fixed

[egk2374]

I'm running macOS Sonoma with two external monitor via a docking station. The screen saver only plays on my laptop's display and the external monitors stay blank during screensaver.

[Silvio6666]

I am using DisplayLink Manager to connect multiple monitors. It only shows on the built-in display. Using Sonoma 14.6.1.
Please note that any other built-in screensaver is displayed on all spaces with the proper option set. Thanks.

[novotnyJiri]

Issue still persists. I am on Sonoma 14.7 other screensavers work correctly.

[SunSparc]

I am on Sequoia 15.1 on a MacBook Pro with one widescreen Dell monitor. The screensaver is working very well for me on both the MBP and the external monitor.

[ifixr]

Interesting. After a few months of giving up, I tested the screen saver today. It worked only on the main display, not the external, USB-C one. I wonder, is your HDMI?

[ifixr]

PS: coincidentally, I tested a few other screen savers, APple-build ones, and some of them didn't work either, and some of them I believe had a wrong behaviour - such as, mirroring the same image rather than running its own.
Arabesque, Album artwork, Shell, Hello , Flurry, Message - both, different
Drift - only main
Photos, Word of the Day - both, mirror (I believe it used to show different)

Another observation - Matrix or Drift woudln't play on the external at all, even when specifically set to run on it, with "Show on all Spaces" off and another, simpler screen saver on the main display.

[SunSparc]

I am connected to the external monitor via USB-C to a dock and HDMI from the dock to the monitor. If you are using HDMI, you might want to check the cable and see what classification it has. Might not be capable of certain things. You could also try some lower resolutions on the monitor to see if the screensavers work at different resolutions.

[larswakefield]

Have been trying to fix this to little success. My thinking is that having the source code would be the best way to continue diagnosis and fixing. Related issue: #10

Let us know what you think @monroewilliams — great work on this by the way. Great throwback :)

Here is some context if you are curious about my issue:

Environment

• macOS 15.x (24F74), Apple M4 Pro
• External: Samsung Odyssey Neo G9 G95NC, 7680×2160 @ 120 Hz (HDR on/off tested)
• Matrix 1.1.5 (also tried 1.1.3/1.1.4)
• Behavior: Matrix renders only on main display. The other display is black. If I switch which display is “Main,” Matrix renders there (so only one screen ever renders).

What I tried

• Renderer: OpenGL and Metal (both show the same single‑display behavior)
• macOS settings: HDR off/on; refresh 60/120 Hz
• Invoking ScreenSaverEngine directly: open -a ScreenSaverEngine (same behavior)
• Windowed test: ScreenSaverEngine -module org.indirect.screensaver.Matrix -window is killed on macOS 15
• Ensured the user-installed saver is used (~/Library/Screen Savers/Matrix.saver)

Proposed fix (note I had to infer these but believe they are roughly on track)

• Per-view/per-display state: avoid any process-global singletons tied to NSScreen.main
• Use the view’s self.window.screen for bounds/scale per instance; honour backingScaleFactor
• Per-view timing: bind a display link to the hosting screen (modern NSView/NSScreen displayLink APIs on macOS 15+ or one CVDisplayLink per view tied to that CGDisplay)
• Rebuild render resources on screen move (viewDidMoveToWindow / screen changes)

Happy to test any build on the G95NC and share logs.

[egk2374]

So interestingly a few months back this started working on all of my displays. At first I figured a macOS update was responsible, but seeing as the bug still says 15.x - which I'm also running - my best guess now would be that I think I changed my primary display to one of the externals and that might be what made it start working on all three. Worth a try for anyone looking for a workaround.

[larswakefield]

So interestingly a few months back this started working on all of my displays. At first I figured a macOS update was responsible, but seeing as the bug still says 15.x - which I'm also running - my best guess now would be that I think I changed my primary display to one of the externals and that might be what made it start working on all three. Worth a try for anyone looking for a workaround.

Thanks. Interesting you got it working on all three. For me it only seems to work on my single external if I make it the main display. I'll try on my other 32:9 tomorrow and see if I have the same issue. Could just be something with the SUW resolutions.

[felder]

Noting that this issue with multiple monitors remains. I have an M5 MacBook Pro running MacOS 27 with 3 monitors and the screensaver seems to randomly work. Sometimes on one monitor, sometimes two, sometimes all 3, sometimes none.

This has been the case for years (not on an M5 of course), but in general. This behavior has occurred on every machine I've had where I've tried this screensaver over many years.