Fixing Safari not responding problem

Do I have to uncheck the option?

Google it, install, you'll be happier.

I fixed the not responding issue ages ago by disabling loads of the experimental features in the develop menu. Mostly the API related ones. I haven't noticed any negative effects of doing this; it just got rid of the not responding and made page loading faster overall.
Make sure show develop menu in menu bar is checked in safari preferences first.
Chris

I have the not responding problem on my MacOS 13, 2017 iMac Pro. I went to the Safari menu bar development>experimental menu and read through the entire list. None were checked, and they were all dimmed.

Damn was I excited to see this tip.

Double damn was I at finding that it made no difference.

Oh well, I guess it was worth the time to try... and certainly worth sharing in case it was the golden bullet.

Well it did fix something, just not the Safari not responding issue. You know how some tables block VO cursor movement? Example: you can't go beyond end of row in App Store receipt emails. Well, this option is the happy fix! So, erm, thanks! :-)

I went in the develop menu and turned off all of the experimental features. Boy, there are lots of them and it took a while. Safari hasn't stopped responding since, but now I can't play youtube videos. Does anybody know which experimental feature youtube playback is tied to, so I can just enable that one? I can watch them in chrome fine, but I prefer safari all day.
Thanks in advance!

Hi all,

I regret to report that safari not responding is happening on my brand new Mac Studio Ultra, which makes me wonder if the problem is something other than cpu or unified memory.

Hi John
I would suggest turning back on all those that start with Media or mention video or decoder. Also all the ones that start with Web except the ones that mention animation.
I would create a list of them all and which ones I have on but there is so many and I am not writing them all out manually.
Thanks
Chris

Well it worked for me

Problem is it's going to take me hours to navigate to the menu, focus VO on each one, copy last phrase to clip board then paste each one into a list.
I never advised turning them all off, just use common cense about which ones to turn off that could be interfering with VO.
I will do more investigation later but be assured it is possible to fix the not responding issue and still have a functional browser.
Chris

Might work. Save lots of time if it does.

Ok it took me a while but here are all the experimental features I have turned off. Some will already be off by default. Ones I feel are important to have off and/or make a difference to the speed of safari with VO are marked with *. Some features are irrelevant to us such as animations or HDR media capabilities so no harm having them off.

• Enable @page support
• Allow per media element speaker device selection
• Allow speaker device selection
• Enable built-in WebKit managed notifications
• CSS 3D Transform Interoperability
• CSS @counter-style image symbols
• CSS @counter-style
• CSS Container Queries
• CSS Custom Properties and Values API
• *CSS Gradient Interpolation Color Spaces
• CSS Motion Path
• CSS Overscroll Behavior
• CSS Painting API
• CSS Relative Color Syntax
• *CSS Spring Animations
• CSS Typed OM
• CSS color-contrast()
• CSS color-mix()
• CSS overflow: clip support
• *CoreImage-Accelerated Filter Rendering
• *Experimental MediaSource Inline Painting
• FTP support enabled
• *GPU Process: DOM Rendering
• *GPU Process: WebGL
• *HDR Media Capabilities
• HTML model element
• HTML model elements for stand-alone document
• *Highlight API
• Incremental PDF Loading
• *Lazy iframe loading
• *Lazy image loading
• *Link preload responsive images
• *LinkPrefetch
• *MediaRecorder
• Paint Timing
• PerformanceNavigationTiming
• PerformanceResourceTiming.transferSize, encodedBodySize, and decodedBodySize
• Permissions API
• *Prefer Page Rendering Updates near 60fps
• Private Click Measurement Debug Mode
• Quirk to prevent delayed initial painting on sites using Google's Anti-Flicker optimization
• ReadableByteStream
• *Remote Playback API
• Resize Observer
• Resolution media feature
• *ScreenCapture
• Scroll To Text Fragment
• Server Timing
• *Service Worker Navigation Preload
• SharedWorker
• *SpeechRecognition API
• *Storage API
• *Swap Processes on Cross-Site Navigation
• Track Configuration API
• *TransformStream API
• *Visual Viewport API
• *Web Animations composite operations
• *Web Animations custom effects
• *Web Animations custom frame rate
• *Web Animations mutable timelines
• WebGL via Metal
• WebGL 2.0
• WebRTC H265 codec
• WebRTC SFrame Transform API
• *WebXR Augmented Reality Module
• WebXR Device API
• WebXR Gamepads Module
• WebXR Hand Input Module
• requestIdleCallback
• Web Inspector Extensions

HTH. Chris

Hi everyone. Thanks for this thread, an issue that is near and dear to my heart.

I checked the enigmatic grouping checkbox, then also upgraded to Mac OS 15.5. After these changes, I did my usual morning web browsing calisthenics, during which I typically encounter "Safari is not responding" multiple times. But with these recent changes, I didn't receive the message once.

Here's a typical situation where I would have encountered the problem. I would go to the New York Times website nytimes.com, select an article to read, and immediately press Command+Shift+R to switch to reader mode. Very often, that would generate a "Safari is not responding" message. But I read multiple articles this morning and didn't get that message.

However, there does seem to be some lag after pressing Command+Shift+R before VoiceOver can access the reader view content. I would think that switching to reader view would be an instantaneous operation, and, back when I could see, the visual switch was indeed instantaneous, even though VoiceOver was telling me "Safari is not responding". I'm no longer able to see any visual content, so can't comment on what's happening visually now. But VoiceOver still seems to lag,, indicating that VoiceOver is still doing something horribly inefficient under the hood. We're just no longer getting the "Safari is not responding" announcement.

Only a couple hours after my previous post, and I've already encountered the "Safari is not responding" message twice. Further evidence the issue isn't completely resolved.

I've continued to give thought to the Group Items Within When Navigating Web Tables setting.

If this setting really applies only to the grouping behavior of tables, and if this setting were to actually reduce the "Safari is not responding" announcement, then it stands to reason that we would only encounter this issue when loading websites with tables. But, in my experience, the "Safari is not responding" announcement often occurs when loading websites that contain no tables at all. So, for those of us who claim to see some benefit from this setting, I have no explanation.

Many of us have reported this issue to Apple, who has acknowledged it's a bug. What we haven't heard yet is where the issue came from or why it occurs, what the reasoning was behind the change from "busy busy busy" to "Safari is not responding", or any schedule for the issue's eventual resolution.

Let us not forget. The problem isn't safari not responding. The problem is, [insert app name] not responding.

Just off the top of my head, I've encountered:
Logic Pro not responding;
mail not responding;
apogee not responding;
sibelius not responding;
pages not responding;
and,
others I don't recall offhand.

I suspect the not responding message is a courtesy offered by voiceOver for delay caused by voiceOver. Our sighted neighbors don't see not responding messages, right? Therefore, the message is inserted by VoiceOver.

I would be inclined to suspect that the not responding message is computer delay having nothing to do with VoiceOver except that there is no apparent change in the processing delay between a 2017 iMac Pro 8 core and a Mac Studio Ultra 16 core. Thus, as I believe Paul previously mentioned, the hang is happening because of a processing jam caused by the VoiceOver app.

I'm curious -- has anyone tried a different screen reader to see if the not responding problem occurs?

Bruce