Closing a window leaves the space until mouse click since 0.18 upgrade

[jayjanssen]

Since upgrading to v0.18 I've noticed what I think is a change in behavior, though I only started using Aerospace on 0.17.

When I close a window now (say with Command-w), I notice that Aerospace will leave the other windows on the screen at the same size and a gap where the previous window was. If I click my mouse anywhere, the remaining windows resize to consume the empty space. However, I can do something like Command-space to open spotlight and start a new app that will go into the empty slot instead if I want.

Is this a feature or bug? Is there an option to adjust the behavior? I would swear the remaining on-screen windows resized immediately in 0.17. I did not see any mention of this in the 0.18 release announcement

[nikitabobko]

AeroSpace has a reactive architecture. AeroSpace reacts to: macOS AX notifications, mouse events, keyboard events.

When you close a window, normally, macOS sends AX kAXUIElementDestroyedNotification notification and/or NSWorkspace.didActivateApplicationNotification. The problem is that notifications are very unreliably in macOS, macOS may delay the notifications, deliver them in inconsistent order, or not deliver them at all.

That's why you observe that AeroSpace normalizes its state only when you click the mouse (alternatively, you could trigger any innocent AeroSpace command like focus right/left, which would also normalize AeroSpace state)

Under some circumstances, notifications are more reliable than under others. For example, it's known that usage of some accessibility applications (like Contexts.app) may affect the delivery of AX notifications.

On my machines (I have multiple of them, and they have different macOS versions), notifications are mostly delivered, and I very rarely see that AeroSpace doesn't normalize its state timely. But my configuration is very minimal. I only use AeroSpace with no bars + karabiner-elements. You are free to explore what affects AX notifications on your system and report back

[jviall]

I'm experiencing this issue as well, but after closing a window (e.g. with Cmd-W) the space remains empty even after clicking or invoking some other trigger (navigating to and from the given workspace), and I have to manually resize the window to correct it.

[jviall]

Additionally, if I try to manually resize the window to full screen by double clicking its top border, it does so but ignores the gutters/margins I've configured for windows, and then when I re-navigate to the same workspace, it resizes back to having the empty gap of the window that was closed. Only clicking and dragging to resize seems to persist.

[nikitabobko]

The reason why it "worked better" in 0.17 version is because AeroSpace was slower at processing the events. And when a lot of the events queue up, it could take a while for AeroSpace to process them. The time it spent processing the events was enough to accidentally observe that the window has became dead. Essentially, it was a race.

[jayjanssen]

I guess that's what you get for making it faster :)