Sleeping tabs FAQ

What is sleeping tabs?

To improve memory and CPU utilization of the browser, we've developed a feature called sleeping tabs.

To free up resources for active tabs, new tabs, and other applications on your device, sleeping tabs in Microsoft Edge makes background tabs “go to sleep” after 2 hours of inactivity. You can adjust the time interval in Settings by going to edge://settings/system. Sleeping tabs will fade to indicate they’ve released resources. To resume a sleeping tab, click on it like a normal tab. The tab will un-fade and your content will be there immediately.

What about the sites I never want to sleep?

To keep you in your flow, we have built in heuristics to detect tabs doing important activity in the background and prevent these tabs from sleeping. You can also add sites you never want to sleep to a block list in Settings by going to edge://settings/system.

What activities prevent a site from going to sleep?

To help you stay on task and limit potential compatibility issues, the following activities prevent sites from going to sleep:

• The page is currently visible (active tab)
• The page is currently holding a Web Lock or an IndexedDB transaction
• The page is sharing its BrowsingInstance with another page
• The page is your company’s internal (intranet) site
• The page is currently being inspected by DevTools
• The page is currently playing audio
• The page is currently capturing a window or screen
• The page is currently capturing user media (webcam, microphone, etc)
• The page is currently being mirrored (casting, etc)
• The page is on the user’s block list in Settings
• The page is currently using WebUSB
  

We will continue to evolve this list as needed.

How does the sleeping tabs technology work?

Sleeping tabs builds upon the core of Chromium’s “freezing” technology. Freezing pauses a tab’s script timers, minimizing CPU usage and frees up the operating system to reuse the memory for other open tabs, new tabs, or system applications.

What is the difference between a sleeping tab and a discarded tab?

For a sleeping tab, the page is simply "paused", allowing Microsoft Edge to release some system resources. Specifically, sleeping minimizes the CPU usage to the bare minimum which helps reduce the battery consumption as well as release some of the memory.  The advantage of sleeping a tab is that going back to it again is very fast and imperceptible.

A tab can also be discarded. When a tab is discarded, the content of the page is completely thrown away, allowing all of the resources (CPU, memory) to be released. The downside here is that the page needs to be fully reloaded when going back to that tab.

What sleeping tabs group policies will enterprises get?

We offer group policies to:

• Enable and disable the feature all-up
• Manage the time before an inactive tab goes to sleep
• Manage which sites should be blocked from going to sleep

These can be both mandatory or recommended group policies. If it’s a recommended group policy, IT admins will have the ability to set the default behavior that their users can change later, if they wish.

Why do others see the feature, but I do not?

We're in the process of deploying this feature, so it may be a little while before you see it in your respective channel and build. 

Can I turn off sleeping tabs?

Yes, you can do this by toggling off in Settings under edge://settings/system.

Can I change the amount of time before a tab goes to sleep?

Yes, you can do this by changing the time interval in Settings under edge://settings/system.

How do I send feedback?

It’s possible some sites might not work as expected after they go to sleep. We’ve built heuristics to detect these scenarios and prevent those tabs from sleeping to keep you in your flow. We’re eager to get your feedback on sleeping tabs. If you experience a tab that doesn’t wake up as you expected, please refresh the page and let us know by pressing Alt+Shift+I on a Windows device or going to Settings and more … > Help and feedback > Send feedback.

You can also discuss your experience here on the Microsoft Edge Insider forums and Twitter, or send us your feedback through the browser!

- The Microsoft Edge Product Team