Thanks, Chrome: resource-intensive ads may soon be blocked by the browser

Google Chrome Canary on Android device
Google Chrome Canary on Android device (Image credit: Android Central)

What you need to know

  • Google is testing a new 'Heavy Ad Intervention' feature for the Chrome browser.
  • It automatically disables ads that consume excessive amounts of system resources.
  • The feature is currently only available via a flag on the Canary builds for Chrome 80.

Ever had your system slowed down unexpectedly while browsing the web? Cryptomining ads ⁠— or just poorly optimise ones —may be to blame. And Google wants you to know that it's got your back, by blocking these 'poorly performant ads automatically.

The Canary builds for Chrome 80 now feature a new flag called 'Heavy Ad Intervention' (via Techdows). As the company's engineers explain,

"A small fraction of ads on the web use an egregious amount of system resources. These poorly performant ads (whether intentional or not) harm the user's browsing experience by making pages slow, draining device battery, and consuming mobile data (for those without unlimited plans). ... The user agent will unload ads that use an egregious amount of network bandwidth or CPU usage. We define egregious as using more of a resource than 99.9% of ads as measured by the browser. Only ads that have not been interacted with by the user will be unloaded."

The company notes that while this is a heavy-handed intervention, it poses little risk to the user's experience while browsing, as unloading an ad does not disrupt the content on the main page. The Explainer page for the feature also notes that only ads that exhibit excessive resource usage without user interaction will be unloaded, meaning if the power-hungry behaviour is initiated only after you've tinkered with the ad, it won't be blocked.

In terms of what kinds of ads Google is looking to block, it notes the following four types of offenders:

  • Ads that mine cryptocurrency
  • Ads that load large, poorly compressed images
  • Ads that load large video files before a user gesture
  • Ads that perform expensive operations in javascript, such as decoding video files, or CPU timing attacks

The welcome addition to the browser is, however, only available to power users and tinkerers who are on the Canary builds of Chrome 80. Even then, it's hidden behind a flag that you need to toggle on manually. You can do so by inputting chrome://flags/ into the URL bar and searching for 'Heavy Ad Intervention'. There's no indication yet as to when the same will be released to stable builds of the browser, though if you're rocking Chrome Canary, you can access the flag on virtually all of the platforms Chrome supports: Android, Windows, macOS, Linux, and of course, Chrome OS.

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