AltTab Unresponsive for 5-15 seconds, every few minutes

[timothyvermeiren]

Describe the bug

When pressing the shortcut for AltTab (CMD + Tab or CMD + ` for same app), AltTab does not respond until after a few seconds, sometimes up to 15 seconds. This may or may not be a follow-up of #3845 and #3986, which I've experienced as well. In this case, this happens virtually every other time I'm trying to alt-tab, or every few minutes.

At this stage, I'd even switched to a view with no thumbnails (the list view) hoping that it would mitigate the issue previously caused by accessing screen recording, but that does not seem to be related.

Update 15:53 CET: I took away the app's screen recording permissions to test whether this is related, but it turns out that the behavior does not change; i.e. still gets stuck even when the permission is not granted.

Update 15:58 CET: for what it's worth, I'm also noticing this while the selector is already open. I.e. AltTab immediately shows and I start tabbing through windows, but it gets stuck after a few tabs. See the screenshot below, though it doesn't say much... but it does have the spinning beach ball, which isn't captured.

Screenshots / video

Video:

CleanShot.2025-01-16.at.15.26.48.mp4

Spindump (from an occurrence before the one on video):

Spindump AltTab 2025-01-16.txt

Occurrence with selector open (imagine the spinning beachball on here, which isn't visible in the screenshot):

Steps to reproduce the bug

Regular usage of AltTab.

Your environment

• AltTab version: 7.19.1
• macOS version: 15.1.1
• Other relevant info: Using external monitor (Asus Zenscreen), but no other peripherals.

[lwouis]

Unfortunately, I don't see much in the spindump. I notice:

Duration: 15.80s
Duration Sampled: 10.01s (process was unresponsive for 6 seconds before sampling)

Could you please try and send me another spin dump? Maybe even a second or third one? Hopefully it can capture what's going on at the time of the freeze.

Thank you

[Lexxie9952]

After update, I can only use Alt-tab for a short time after booting up. After that, my shortcut to do it doesn't function at all.
Going into Activity Monitor I see Alt-tab shows as not-responsive.

I'm going to look to see if I can roll back otherwise I have to stop using it.

[lwouis]

@Lexxie9952 please share a spindump when it's unresponsive 🙇