WezTerm Freezes on Launch with 100% CPU Usage on macOS 15.4

[nasyxx]

What Operating System(s) are you seeing this problem on?

macOS

Which Wayland compositor or X11 Window manager(s) are you using?

macOS 15.4

WezTerm version

wezterm 20250320-072107-a8735851

Did you try the latest nightly build to see if the issue is better (or worse!) than your current version?

Yes, and I updated the version box above to show the version of the nightly that I tried

Describe the bug

After upgrading my system to macOS 15.4 beta, WezTerm freezes immediately upon launch with 100% CPU usage. Initially, I thought this might be related to issue #6738 , but now I believe it may only be partially related or possibly a separate issue altogether. Since macOS 15.4 has now reached Release Candidate status, I'm creating this new issue to track the problem.

To Reproduce

The issue is consistently reproducible: WezTerm freezes immediately whether launched via command line from another terminal or by clicking the application icon. I've attempted to troubleshoot by removing all configurations and launching with the -n flag, but the freezing persists in all scenarios.

I'm not certain what debug information would be most helpful, but I'm willing to provide any necessary details to assist with resolving this issue. Currently, WezTerm is completely unusable for me, which is particularly frustrating as it's my preferred terminal emulator.

Configuration

no config

Expected Behavior

No response

Logs

> wezterm -n
2025-03-26 23:38:29.315 wezterm-gui[5106:10413722] NSKeyBindingManager: Bad key binding selector for '^$/' = 'redo:'
2025-03-26 23:38:29.315 wezterm-gui[5106:10413722] NSKeyBindingManager: Bad key binding selector for '^x' = '{
    "[" = "pageUp:";
    "]" = "pageDown:";
    u = "undo:";
}'
2025-03-26 23:38:29.315 wezterm-gui[5106:10413722] NSKeyBindingManager: Bad key binding selector for '^/' = 'undo:'
fish: Job 1, 'wezterm -n' terminated by signal SIGTERM (Polite quit request)

Anything else?

No response

[techyogi]

seeing this as well.

[adyshev]

same here, sequoia 15.4, wezterm stopped working with the same symptoms.

[nasyxx]

I found it works with sudo wezterm. Then I created a new user and it ran as usual.

After that, I closed a lot of running apps to see if there was a conflict. Finally, I found that PopClip may have some conflicts with Wezterm.

So, now I added wezterm to excluded app in popcilp, and wezterm works.

[odyshev]

Good catch, @nasyxx ! Confirmed. Thank you so much!

[ESMP]

Wow... kudos to you @nasyxx, it works again when excluding from PopClip.

[bew]

Good catch on find the issue with PopClip! Did you upgrade this app recently?

Was it working in Wezterm before? (if not, then I think we can close this issue)

[ESMP]

Good catch on find the issue with PopClip! Did you upgrade this app recently?

Was it working in Wezterm before? (if not, then I think we can close this issue)

Yes, just before macOS 15.4, WezTerm (v20240203-110809-5046fc22) didn't have any issue with PopClip (v2024.12).

[bew]

Can you try with the last stable version on Wezterm (from last year, not nightly), see if there is a regression?

I'd also suggest contacting PopClip's support to try and get more information on this issue.

[nasyxx]

Can you try with the last stable version on Wezterm (from last year, not nightly), see if there is a regression?

The released version, including download bin / build from scratch / Nix, is still stuck.

[techyogi]

Always possible that something is conflicting but the likely culprit is Macos 15.4 itself. Something changed. I tried the older stable - hangs. Nightly - hangs. I dont' have popclip, but just to see i disabled Alfred, Raycast, Karabiner, and every other keyboard control or extension... same issue - hang.

[bew]

My work Mac got upgraded to 15.4 yesterday and I personally do not see this behavior with last release 😬 (will try nightly / nix build when I can)

(I don't have PopClip nor Keycue)

[ChristinWhite]

I'm seeing a very similar behavior. After starting Wezterm it doesn't freeze on startup, but it does freeze after I type in a few characters. It also doesn't hammer my CPU, but Wezterm becomes completely unresponsive, it beachballs and I have to force quit it.

I don't have PopClip installed, but that got me headed in the right direction and I eventually tracked it down to Keycue being the incompatibility, once I quit that Wezterm functioned normally again.

[techyogi]

Interesting... KeyCue was the culprit for me... works once uninstalled.

[Myran]

Have the same problem however yet to find the culprit. edit: it was the chatgpt app

[bew]

So basically the issue seems to be with apps that try to be smart with text input areas in all apps 🤔

It would be interesting if you see a similar behavior with other terminals

[carlca]

I can confirm the lockup with macOS 15.4. I also found that quitting KeyCue was enough to get WezTerm up and running again. This appears to happen both with stable and nightly WezTerm.

I also use, from time to time, Warp and Wave. No problems there...

[pyrho]

I have 100% repro with Alfred's Menu Bar Search Workflow, triggering this workflow makes Wezterm (nightly version 20250320-072107-a8735851) freeze indefinitely.

[Myran]

Had no issues with macos terminal while wezterm locked up. Mac mouse fix also seemed to trigger the issue

[Amparose]

wezterm: 20240203-110809,5046fc22 on 15.4 is completely unusable for me too. Quit PopClip but I do have a fair few utility apps running so maybe processes trying to use MacOS accessibility API or the menu lib thing on Wezterm cause it to crash?

[almeidainf]

I can reproduce, and it seems like Raycast was the culprit in my case - mixed in with Apple Intelligence stuff. Here's what else I learned:

MacOS 15.4 (24E248) Wezterm Stable 20240203-110809-5046fc22 - reproducible Wezterm Nightly 20250320-072107-a8735851 - reproducible

Method 1

1. Open Wezterm. It works fine while it's still the focused window.
2. Change focus to another window. Wezterm is still fine according to htop running on another terminal emulator.
3. Focus back to Wezterm window. Wezterm becomes unresponsive and htop reports 100% CPU usage.

Method 2 I can also reproduce #6864 mentioned above.

1. Open Wezterm.
2. Go to the Edit menu, hover over Writing Tools. Wezterm becomes unresponsive and htop reports 100% CPU usage.
3. When reproducing it this way, the macOS dock also stops coming up (I have it hidden). Killing the dock process brings it back.

Disabling Apple Intelligence fixes the issue.

I reenabled Apple Intelligence and started hunting down background applications. I couldn't reproduce method 1 after killing Raycast. Weirdly enough, I brought Raycast back and still couldn't reproduce method 1. It even survived a reboot.

So it seems like Raycast was doing something that it isn't doing anymore after a restart of the process. I bet it will come back though, I will report back when it does.

[pyrho]

Thanks @almeidainf, I can confirm that disabling Apple Intelligence fixes the issue for me.

[techyogi]

sounds like wezterm could use an update... no other terminal has this issue that i've tested.

On Tue, Apr 15, 2025 at 2:01 AM Damien Rajon @.***> wrote:

Thanks @almeidainf https://github.com/almeidainf, I can confirm that disabling Apple Intelligence fixes the issue for me.

— Reply to this email directly, view it on GitHub https://github.com/wezterm/wezterm/issues/6833#issuecomment-2804174782, or unsubscribe https://github.com/notifications/unsubscribe-auth/AAAC6MNBLNFXIBRXKSDSCPT2ZS4ETAVCNFSM6AAAAABZ37BN2GVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMBUGE3TINZYGI . You are receiving this because you commented.Message ID: @.***> pyrho left a comment (wezterm/wezterm#6833) https://github.com/wezterm/wezterm/issues/6833#issuecomment-2804174782

Thanks @almeidainf https://github.com/almeidainf, I can confirm that disabling Apple Intelligence fixes the issue for me.

— Reply to this email directly, view it on GitHub https://github.com/wezterm/wezterm/issues/6833#issuecomment-2804174782, or unsubscribe https://github.com/notifications/unsubscribe-auth/AAAC6MNBLNFXIBRXKSDSCPT2ZS4ETAVCNFSM6AAAAABZ37BN2GVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDQMBUGE3TINZYGI . You are receiving this because you commented.Message ID: @.***>

-- Benjamin Sanders e: @.*** @.***> | m: 917.817.9495

[Amparose]

MacOS 15.4.1 seems to have fixed this for me. Others seeing the same?

[carlca]

I'm on macOS 15.4.1 and WezTerm is still freezing after a few keystrokes if KeyCue is running. Quitting KeyCue enables WezTerm to run okay, it seems,

I should also point out that I have the very latest version of Raycast1 - v1.96 - running and that doesn't seem to be affecting WezTerm.

[pyinto]

MacOS 15.4.1 seems to have fixed this for me. Others seeing the same?

nope, still having the same issue. But can confirm that turning off apple intelligence indeed helps at first glance, will keep posted.

[pyinto]

I'm on macOS 15.4.1 and WezTerm is still freezing after a few keystrokes if KeyCue is running. Quitting KeyCue enables WezTerm to run okay, it seems,

I should also point out that I have the very latest version of Raycast1 - v1.96 - running and that doesn't seem to be affecting WezTerm.

Do you have Apple Intelligence features active? For me it was also bugged when some app (Raycast in my case) is trying to access "writing tools" menu for WezTerm, now it's disabled and seems to work fine. But when enabled even with no any third party app running, click on top menu dropdown freezes it.

[pyinto]

I can reproduce, and it seems like Raycast was the culprit in my case - mixed in with Apple Intelligence stuff. Here's what else I learned:

MacOS 15.4 (24E248) Wezterm Stable 20240203-110809-5046fc22 - reproducible Wezterm Nightly 20250320-072107-a8735851 - reproducible

Method 1

1. Open Wezterm. It works fine while it's still the focused window.

2. Change focus to another window. Wezterm is still fine according to htop running on another terminal emulator.

3. Focus back to Wezterm window. Wezterm becomes unresponsive and htop reports 100% CPU usage.

Method 2 I can also reproduce #6864 mentioned above.

1. Open Wezterm.

2. Go to the Edit menu, hover over Writing Tools. Wezterm becomes unresponsive and htop reports 100% CPU usage.

3. When reproducing it this way, the macOS dock also stops coming up (I have it hidden). Killing the dock process brings it back.

Disabling Apple Intelligence fixes the issue.

I reenabled Apple Intelligence and started hunting down background applications. I couldn't reproduce method 1 after killing Raycast. Weirdly enough, I brought Raycast back and still couldn't reproduce method 1. It even survived a reboot.

So it seems like Raycast was doing something that it isn't doing anymore after a restart of the process. I bet it will come back though, I will report back when it does.

@almeidainf, I have no Raycast running, and can consistently reproduce the issue by accessing the "Writing Tools" menu in WezTerm. This leads me to believe that the problem isn't necessarily caused by Raycast or other applications that indirectly accessing that menu.

Specifically with Raycast, there is a native extension that can display app menus as a single dropdown, which of course requires caching those menu items by accessing them, which will trigger the freeze as if you pressed that menu manually. The same goes for PopClip and any other third-party hotkey navigator app. But the core issue lies in the latest Mac OS patches (I have Apple Intelligence enabled since it was introduced, there were no such issues with WezTerm app for quite a while).

Perhaps WezTerm could consider an option to exclude the Writing Tools menu altogether if possible, or simplify it's default behavior, I feel like all the raw data of your current session be sent to local AI when you hover that menu. This isn't right, and not WezTerm to blame for, but would be great to see some workaround. This is just my speculation, there are apps where accessing that menu doesn't cause any issues, that's why I belive it's possible to fix it on WezTerm end, even though it's not their fault.

[carlca]

I'm on macOS 15.4.1 and WezTerm is still freezing after a few keystrokes if KeyCue is running. Quitting KeyCue enables WezTerm to run okay, it seems, I should also point out that I have the very latest version of Raycast1 - v1.96 - running and that doesn't seem to be affecting WezTerm.

Do you have Apple Intelligence features active? For me it was also bugged when some app (Raycast in my case) is trying to access "writing tools" menu for WezTerm, now it's disabled and seems to work fine. But when enabled even with no any third party app running, click on top menu dropdown freezes it.

@pyinto Interesting! KeyCue was certainly stopping WezTerm running, but following your comment, I've just disabled Apple Intelligence and now I can run WezTerm and KeyCue at the same time. This is starting to defy logic, somewhat 😮😉

[wiggly-sheets]

Also have been having this problem for some time now, at least a few weeks. Looking through this thread, I only have Raycast and Apple Intelligence out of the problem app/services (no Popclip or Keycue), and quitting Raycast seems to solve the issue. Even with Raycast quit, however, I still have the issue of hovering over writing tools causing the same issue. A way around this might be to disable "search menu items" in Raycast window management settings, however I really like this feature and use it often. Edit: I also use the app menuwhere to get the Apple menu and current app's menu items at my mouse location. Hovering over writing tools in Menuwhere also triggers the same issue, when Wezterm is the active app. Hovering over it in other apps is not an issue.

[iesahin]

Another data point: Wezterm started to freeze after I started to use Raycast. macOS 15.4.1 on MBP M1, Raycast 1.97.0 and wezterm 20240203-110809-5046fc22