USB-C hub and dock guide
Mac windows often rearrange when a monitor on a USB-C hub or dock flickers, sleeps, or reconnects, because for that moment macOS sees the monitor as unplugged and moves its windows to a display that is still there. When the monitor comes back, the windows usually stay where macOS put them. Free fixes can make the connection steadier. If they do not, SnapState can restore a saved layout automatically when the monitor reconnects.
Recommended fix: SnapState. Save your layout once and SnapState puts windows, apps and browser tabs back whenever the hub monitor returns. $9.99 one-time, up to three Macs. See the guide to windows rearranging when you connect a dock.
Short version: a hub that drops the video signal for even a second looks like a cable being pulled, so macOS moves the windows and leaves them there. Try the free fixes below first. If the flicker keeps happening, let SnapState put the layout back each time.
A USB-C hub or dock carries the video signal to your monitor alongside power, USB devices, and networking. A loose connector, a cable near its limit, a hub that runs short on power, or a monitor that drops into deep sleep can all make the signal cut out briefly. Each time it does, the monitor can disappear from macOS for a moment, which looks the same as unplugging it.
macOS generally responds by moving the windows from the missing display onto one that is still connected, often the built-in laptop screen. When the hub brings the monitor back, macOS re-detects it but does not reliably send each window back to its earlier display and position. It is the same behavior as windows moving after you unplug a monitor, just triggered by the hub instead of your hand. If your dock uses DisplayLink, see DisplayLink windows moving after sleep, and if the pile-up only happens after the Mac sleeps, see windows moving to one screen after sleep.
These are worth trying before you pay for anything. Results vary by Mac, hub, cable, and monitor.
SnapState is a native macOS menu bar app. A workspace captures the windows on every Space with their position and size, the apps needed to relaunch them, the monitor and display layout, and all open tabs of each window in Safari, Chrome, Edge, Brave, Arc, and Chromium once Automation permission is granted. If the hub monitor is still missing when a restore runs, saved window frames are remapped onto the displays you have now, and the monitor connect trigger puts things right once it returns.
The same approach helps if your windows rearrange when you switch your monitor input or an iPad Sidecar display connects or drops.
SnapState costs $9.99 as a one-time purchase, with a lifetime license for up to three Macs. Version 2.7.2 requires macOS 15.7 or later on Apple Silicon and Intel Macs and ships as a signed, notarized DMG rather than through the Mac App Store. It needs Accessibility permission to move windows, and workspace data stays local on your Mac as JSON in ~/Library/Application Support/SnapState/.
SnapState cannot repair a faulty hub, cable, or monitor, so it does not stop the flicker; it restores the layout after it. It restores layouts across multiple Spaces (apps go back to the Space they were saved on, full-screen windows return to full screen, and windows on other Spaces are placed when you switch to them). Firefox is not supported, and tabs are restored only from supported browsers. It is not a tiling or snapping window manager, and it requires macOS 15.7 or later.
A flicker is often a short disconnect. When a USB-C hub or dock briefly loses the video signal, renegotiates it, or resets, the monitor can vanish from macOS for a moment. macOS treats that as a disconnected display and moves its windows onto a screen that is still there, then usually leaves them there when the monitor returns a second later.
Many monitors power down deeply when they sleep, and a hub may stop reporting the display until it wakes. When the monitor comes back through the hub, macOS sees a new connection and does not reliably send each window back to its earlier display and position.
Try a different port on the Mac, a shorter or higher-rated USB-C or HDMI or DisplayPort cable, connecting the monitor directly instead of through the hub, giving a powered hub its own power supply, and updating the hub or dock firmware if the maker offers it. In the monitor on-screen menu, options for deep sleep or automatic input detection can also matter. Results vary by hub and monitor.
Save a workspace while the hub monitor is connected and every window is where you want it, then arm the monitor connect or matching display layout trigger, and wake from sleep if needed. When the monitor reappears, SnapState moves the saved windows back, relaunches missing apps, and remaps saved frames onto the current displays if the setup differs.
SnapState is $9.99 as a one-time purchase, with a lifetime license for up to three Macs. There is no subscription.
SnapState cannot fix a faulty hub, cable, or monitor, so it does not stop the flicker itself; it puts the layout back after it. Firefox is not supported, tabs are restored only from supported browsers, it is not a tiling or snapping window manager, and it requires macOS 15.7 or later.
The same pile-up happens in clamshell mode and on an ultrawide. One way to put a whole desk back is a multi-monitor shortcut. For tiling rather than restore, see Rectangle, Magnet, and Raycast.