Concern over ad viewability is growing and a new feature in the Google Chrome browser is only likely to increase those concerns.

The feature makes a determination as to whether Flash content is ‘central to the webpage’. If it is, the Flash content will be displayed normally. If it isn’t, Chrome will pause the display of the Flash content.

Should the Chrome feature interrupt the display of desired content, users can click to resume.

According to Google, pausing extraneous Flash content “significantly reduces power consumption [on laptops] allowing you to surf the web longer before having to hunt for a power outlet.”

While potentially good news for laptop users, Google’s update to Chrome, which is now enabled by default in the latest desktop Beta channel release of Chrome, could be bad news for advertisers already struggling to address concerns over the viewability of their ads.

While Flash’s popularity has waned, some animated display ads still rely on Flash, and Flash is still often used to deliver video content.

It seems that Flash ads are likely to fall under the content that Chrome deems unimportant, calling into question the long-term viability of animated Flash display ads.

Additionally, it’s probable that at least some Flash video containing pre-roll ads will get caught in Chrome’s filters as well, changing the dynamic for advertisers in the booming video ad market.

So what can advertisers do?

Matt Rednor, founder and CEO of agency Decoded Advertising, told Clickz’s Dave Neal and Emily Alford that as far as video is concerned, advertiser efforts should be focused on social:

Social platforms, which are where most people are spending their time anyway, are all rolling out video ad units that are more organically incorporated into the experience, and the Chrome extension won’t block those.

That seems like a sensible approach, but even if Google’s update to Chrome ultimately pushes advertisers and the publishers they buy from to deliver ads that are better integrated into user experiences, the message to advertisers is clear: the viewability conundrum is only likely going to get more complex and costly to address.