[script] Prevent update freezing all windows

[bencat86]

I've been fighting a problem for a little while, where brew upgrade yabai causes all windows to freeze. The fix so far has been to kill yabai (if I happen to have a terminal) or reboot. It seems to be due to a mix of needing to regrant accessibility permissions, and launchd repeatedly restarting a failing yabai process.

I've written a yabai-upgrade helper script (AI assisted) which seems to solve the problem. Posting here in case it helps others. Possibly it can also be integrated into the brew packaging to solve the issue.

Edit: It seems adding this to plist also avoids lock up. Looks like it was in the brew package at some point, but got removed?

<key>ThrottleInterval</key>
<integer>10</integer>

[adithyabhatkajake]

I also had this issue and restarting was the only way I could get my system back. The whole system freezes with the accessibility permission window.

[bencat86]

Summary from my AI assisted investigation/fix. I found it helpful to explain what's going on..

Root cause

╭──────────────────────╮   ╭────────────────────╮   ╭──────────────────────╮
│ brew upgrade yabai   │──▶│ macOS revokes      │──▶│ yabai launches,      │
│ swaps the binary     │   │ Accessibility (sig │   │ calls AX trust check │
│ (signature changes)  │   │ changed)           │   │ → denied → abort()   │
╰──────────────────────╯   ╰────────────────────╯   ╰──────────┬───────────╯
                                                               │ SIGABRT
                                                               ▼
╭──────────────────────╮   ╭────────────────────╮   ╭──────────────────────╮
│ User: mouse moves    │◀──│ WindowServer event │◀──│ launchd KeepAlive    │
│ but clicks/keys      │   │ loop saturated by  │   │ (Crashed=true) +     │
│ are dropped          │   │ relaunch storm     │   │ no ThrottleInterval  │
╰──────────────────────╯   ╰────────────────────╯   ╰──────────────────────╯

The respawn loop runs without an effective throttle because:
- yabai's no-permission path uses abort() → SIGABRT, classified as a crash.
- launchd's ThrottleInterval default (10 s) historically does not apply reliably to crash-driven respawns.
- The plist generated by yabai --start-service ([src/misc/service.h](https://github.com/koekeishiya/yabai/blob/master/src/misc/service.h#L8-L43)) has KeepAlive: { Crashed: true, SuccessfulExit: false } but no explicit ThrottleInterval.

Compounding factors:
- Stale TCC denied entries → macOS silently refuses without showing the popup, so the user can't even break the cycle.
- The plist is written once at first-time service setup and never regenerated by brew upgrade, so historical fixes don't reach existing users.

It seems setting ThrottleInterval forces it to apply to crashes too.

[bencat86]

I have a change ready that should resolve the issue, but can't figure out where to open PRs..
master...bencat86:service-throttle-interval

[asmvik]

You need to stop the service and uninstall it, manually, before running brew upgrade.
Brew installs the new version in a new location on disk, which requires the service to be reinstalled afterwards.
This process invalidates the macOS accessibility permission.

-- see #2086 (comment)

Alternatively use the provided installer script instead of brew.
-- see #2086 (comment)

As always instructions are in the wiki:

https://github.com/asmvik/yabai/wiki/Installing-yabai-(latest-release)#updating-to-the-latest-release

Edit: As for your suggestion; ThrottleInterval has a value of 10 by default.

ThrottleInterval
This key lets one override the default throttling policy imposed on jobs
by launchd. The value is in seconds, and by default, jobs will not be
spawned more than once every 10 seconds. The principle behind this is
that jobs should linger around just in case they are needed again in the
near future. This not only reduces the latency of responses, but it
encourages developers to amortize the cost of program invocation.