The slow demise of Adobe Flash continues this week, as Google announced a policy of "HTML5 by Default" for its Chrome browser.

Later this year, HTML5 will become the "primary experience" on Chrome, if a website offers it, technical program manager Anthony Laforge writes in a Google Groups post. If you visit a site that requires Flash to work, Chrome will display a prompt at the top of the page asking if you want to run Flash. 

Since the Web is not totally rid of Flash, however, and to "avoid over-prompting," Google's browser will still support Flash on the top 10 sites that use it: YouTube, Facebook, Yahoo, VK.com, Live.com, Yandex.ru, OK.ru, Twitch.tv, Amazon, and Mail.ru.

"This whitelist will expire after one year, and will be periodically revisited throughout the year, to remove sites whose usage no longer warrants an exception," Laforge writes.

"While Flash historically has been critical for rich media on the Web, today in many cases HTML5 provides a more integrated media experience with faster load times and lower power consumption," he says. "This change reflects the maturity of HTML5 and its ability to deliver an excellent user experience."

Google also plans to add policy controls for enterprises, allowing users to manage individual site preferences, including the ability to completely disable the feature.

In the fall, Chrome 45 began automatically pausing less-important Flash content like ads, animations, and any "non-central" content. The move "significantly reduces power consumption, allowing you to surf the Web longer before having to hunt for a power outlet," Google said at the time.

Facebook, Vimeo, Netflix, YouTube, and Twitch followed suit, beginning the transition from Flash to HTML5.