Google Chrome Causes Crashing Chaos After Silent Browser Experiment

Google Chrome
After beta testing an experimental feature in Chrome for several months without any major issues, Google decided to flip the switch in its main Stable release, and chaos ensued for hundreds of organizations and thousands of machines. Apparently the experimental feature was not quite ready for prime time, as IT admins suddenly had to contend with a mysteriously broken browser.

For those affected, it was not immediately clear what exactly caused all the ruckus. All they really knew was that tabs were suddenly crashing and showing up as blank. This is referred to as a white screen of death (WSOD) error.

The issue manifested itself on Chrome browsers running on Windows Server terminal setups and through virtual machine setups, such as Citrix, which are common in enterprise networks.

"Our organization with multiple large retail brands had 1,000 call center agents and many IT people affected for 2 days. This had a very large financial impact. We NEED a statement and opt out," a user complained in a Chrome bug tracker thread.

"4,000 impacted in my environment. Working on trying to fix it for 12 hours only to stumble upon this [thread]. Poor form," another user wrote.

After seeing complaints pile up at various online forums, Google fessed up to launching an "experiment" on the Stable release of Chrome.

"The experiment/flag has been on in beta for ~5 months. It was turned on for stable (e.g., m77, m78) via an experiment that was pushed to released Chrome Tuesday morning. Prior to that, it had been on for about 1 percent of M77 and M78 users for a month with no reports of issues, unfortunately. - chrome://flags shows you experiments," a Google engineer wrote.

What caused all the ruckus is a featured called WebContents Occlusion. In an effort to reduce Chrome's hungry appetite for system resources, this features suspends tabs when other windows are on top of the browser, essentially relegating them to background tabs.

Google ended up rolling back the feature last night. If you are still running an affected build and are having problems specific to this issue, you can take matters into your own hands by typing the following into the omnibar and disabling each flag...
  • chrome://flags/#web-contents-occlusion
  • chrome://flags/#calculate-native-win-occlusion
It's not clear why Google decided to quietly test this feature on a Stable release. And even though it's now been rolled back, some of those affected are livid with Google, given what transpired.

"Do you see the impact you created for thousands of us without any warning or explanation? We are not your test subjects," a user wrote. "We are running professional services for multi million dollar programs. Do you understand how many hours of resources were wasted by your 'experiment'? Not acceptable."

Hopefully Google learns from this and makes this sort of thing an opt-in or opt-out affair in the future.