Does safari put inactive tabs to sleep?

[TrancyGoose]

Can't find a definite answer online. Does Safari put the idle tabs to sleep or not? I know most Chromium based browsers do.

 

[bogdanw]

The default configuration is Background Tab Suspension disabled.

defaults read ~/Library/Containers/com.apple.Safari/Data/Library/Preferences/com.apple.Safari.plist WebKitTabSuspension

returns "does not exist"

 

[TrancyGoose]

The default configuration is Background Tab Suspension disabled.

defaults read ~/Library/Containers/com.apple.Safari/Data/Library/Preferences/com.apple.Safari.plist WebKitTabSuspension

returns "does not exist"
View attachment 1942429

I am not very technical, but I assume that was a no, thank you!
Im trying to see if it's worth moving to Edge for example?
Installed Firefox, noticed a massive memory consumption, won't open it again!

 

[frou]

I found this thing a funny example of how Safari is handling active vs inactive tabs.

 

[bogdanw]

To enable Background Tab Suspension
- close Safari
- enable the Debug menu with

defaults write com.apple.Safari IncludeInternalDebugMenu -bool YES

- start Safari and uncheck the Disable Background Tab Suspension seen in the image above
Some info about the Debug menu https://osxdaily.com/2011/11/07/safari-debug-menu/

 

[TrancyGoose]

To enable Background Tab Suspension
- close Safari
- enable the Debug menu with

defaults write com.apple.Safari IncludeInternalDebugMenu -bool YES

- start Safari and uncheck the Disable Background Tab Suspension seen in the image above
Some info about the Debug menu https://osxdaily.com/2011/11/07/safari-debug-menu/

Thank you! Maybe you also know a way for Mac Mail not to show inline attachments? As in preview the 1 page documents in body? There is a command online, but it don't work any more Big Sure and Monterey seem to have changed.

 

[tja0]

To enable Background Tab Suspension
- close Safari
- enable the Debug menu with

defaults write com.apple.Safari IncludeInternalDebugMenu -bool YES

- start Safari and uncheck the Disable Background Tab Suspension seen in the image above
Some info about the Debug menu https://osxdaily.com/2011/11/07/safari-debug-menu/

This does sadly not exist anymore!

I cannot find it in the Debug menu, and also not within the defaults file:

$ defaults read ~/Library/Containers/com.apple.Safari/Data/Library/Preferences/com.apple.Safari.plist | grep -Ei '(background|suspend)' | grep -i tab
$

No result for anything related to background or suspend for Tabs ...

 

[bogdanw]

Might be fixed in the future.
"Bug 255876 - [macOS] PLT ~0.5% regression with background tab suspension"
https://bugs.webkit.org/show_bug.cgi?id=255876

 

[A2084]

December 2023 with macOS Sonoma with Safari 17 and still no Debug option visible 😪

 

[bogdanw]

December 2023 with macOS Sonoma with Safari 17 and still no Debug option visible 😪

If you are referring to the Debug menu, it is not intended for regular users.
You can turn it on as explained in post #5 or with Onyx https://titanium-software.fr/en/applications.html

 

[ksec]

Anyone know if this can be done on Safari 17 or later. The option is gone in debug menu.

 

[bogdanw]

As the option is no longer present in the menu, I doubt this will have any effect.
From Terminal
read

defaults read ~/Library/Containers/com.apple.Safari/Data/Library/Preferences/com.apple.Safari.plist WebKitTabSuspension

write

defaults write ~/Library/Containers/com.apple.Safari/Data/Library/Preferences/com.apple.Safari.plist WebKitTabSuspension -bool YES

delete

defaults delete ~/Library/Containers/com.apple.Safari/Data/Library/Preferences/com.apple.Safari.plist WebKitTabSuspension