Jack Marshall:

Alphabet Inc.’s Google is planning to introduce an ad-blocking feature in the mobile and desktop versions of its popular Chrome web browser, according to people familiar with the company’s plans.

The ad-blocking feature, which could be switched on by default within Chrome, would filter out certain online ad types deemed to provide bad experiences for users as they move around the web.

Google could announce the feature within weeks, but it is still ironing out specific details and still could decide not to move ahead with the plan, the people said.

Unacceptable ad types would be those recently defined by the Coalition for Better Ads, an industry group that released a list of ad standards in March. According to those standards, ad formats such as pop-ups, auto-playing video ads with sound and “prestitial” ads with countdown timers are deemed to be “beneath a threshold of consumer acceptability.”

Some ads are more equal than others.