Chrome Energy Saver and wake locks: why the screen still goes dark

These work in Chrome and Edge on any system. Sources checked 26 September 2026: Chromium’s wake_lock.cc refuses only for a hidden or inactive page, a Permissions-Policy block or a denied permission, and never reads a saver mode.

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   Step 1 · Bring the AwakeTab tab to the front

   Next upChrome › the AwakeTab tab

   Energy Saver slows background tabs, and a hidden tab has no wake lock anyway. Switching tabs or minimising the window releases the lock. A visible window without focus keeps it.

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   Step 2 · Start a session and read the pill

   AwakeTab › Start

   Wait for "Screen awake", which shows only once Chrome has granted the lock. If it says "Blocked — here's the fix", follow the line under it.

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   Step 3 · Check the Windows screen timeout and Energy saver

   Settings › System › Power & battery

   Windows keeps one screen timeout for battery and one for plugged in. Energy saver (Battery saver before Windows 11 24H2) may shorten timeouts or dim the screen on battery, but it does not refuse a browser wake lock.

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   Step 4 · Check the phone's own timeout

   Settings › Display › Screen timeout

   On a Pixel with Android 16, the path is Settings › Display & touch › Screen timeout. Battery Saver may shorten it or dim the screen, but Chrome does not refuse the lock because of it.

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   Step 5 · Confirm the request reached the system

   Terminal › powercfg /requests or pmset -g assertions

   On Windows, run powercfg /requests in an administrator terminal: the browser should be listed under DISPLAY. On a Mac, run pmset -g assertions and look for a PreventUserIdleDisplaySleep or NoDisplaySleep line from your browser.

If the screen still goes dark

With the tab in front and the pill saying “Screen awake”, the cause is outside the browser. These are the usual ones.

• The lid closed A closed laptop lid sleeps the computer whatever a page asks, apart from a Mac in clamshell mode or a Chromebook with "Sleep when cover is closed" turned off.
• A work lock screen appeared A wake lock holds off display sleep, not a "require sign-in after N minutes" policy. On a work computer, only your IT team can change it. Lock screen versus sleep
• The session ended A timed session stops at the time you picked, and your normal timeout takes over. Pick ∞ to run until you stop it.

What each saver changes

Four different switches share the name. None makes Chrome refuse a wake lock, but some change what the system does around it.

• Chrome's Energy Saver Slows tabs in the background. It does not touch the wake lock of the tab you are looking at.
• Windows Energy saver Called Battery saver before Windows 11 24H2. It may dim the screen or shorten timeouts; it does not refuse a browser wake lock.
• Android Battery Saver Chrome has no Battery Saver check on the wake lock. It may shorten your timeout or dim the screen once you leave the tab.
• iPhone Low Power Mode Sets Auto-Lock to 30 seconds. WebKit has no Low Power Mode check; whether a Safari lock holds under it has not been device-tested yet. iPhone Auto-Lock greyed out

To keep the screen on while you work in another tab, use AwakeTab for Chrome on desktop Chrome or Edge.