Stephen Shankland/CNET

Firefox, a browser billing itself as the choice for anyone valuing privacy on the web, is following rivals that led the way with a technology called tracking protection.

With the 2017 release of Firefox 57 -- the first "Quantum" version geared to reinvigorate Firefox's competitiveness with Google's Chrome -- Mozilla made it possible to block website software that tracks you on the web. Trackers can be used so advertisers can build detailed profiles of you and show you an ad that follows you around the web. Trackers also mean websites load more slowly, use your network data and consume more battery power.

"In the near future, Firefox will -- by default -- protect users by blocking tracking while also offering a clear set of controls to give our users more choice over what information they share with sites," said Nick Nguyen, vice president of Firefox, in a blog post Thursday.

Seems like a no-brainer, right? Wrong. The online ad industry has its downsides, but it also has funded countless websites that otherwise wouldn't exist or would charge you money to use. It's not a simple decision, and Mozilla's actions are amplified by the activity of the 250 million of us who use Firefox each month.

Tracking is at risk, though. For one thing, millions of people now use browser extensions like Ghostery and Privacy Badger that block trackers. More importantly, Apple has started blocking some trackers with intelligent tracking protection in its Safari browser, and Brave, led by Mozilla co-founder and former Firefox leader Brendan Eich, blocks all trackers by default.

Blocking trackers can cause problems with some websites, including those that detect the blocking and ask us to disable it. But a Mozilla study in 2017 showed that people reported fewer problems with tracking protection enabled.

And tracking protection is catching on in Firefox. Since the feature arrived in November, people have steadily been enabling it even before Mozilla's future move to turn it on by default. Worldwide, 1.3 percent of people enable Firefox tracking protection today. In the US it's 2 percent, and in France it's 3 percent.

Mozilla didn't define exactly how its tracking protections will work, but it said it'll give people options for two types. First are situations where tracking slows down websites. Second are situations with website tracking from third parties -- in other words, from organizations that are contributing content like ads to the actual publisher of a website.

CNET Magazine: Check out a sample of the stories in CNET's newsstand edition.

Taking It to Extremes: Mix insane situations with everyday tech. Here's what happens.