Ask most Firefox fans what they like about the browser, and they'll probably mention that it's more privacy-friendly than Google Chrome.

But one IT security analyst has found out that the browser is, by default, sharing information about its 198 million users with its developers at Mozilla.

This tracking without consent discovered by online security researcher Mike Kuketz in an analysis of the desktop version of the browser.

This will come as a surprise to many Firefox fans, who have heard many claims that Mozilla takes extra effort to protect user privacy.

"Mozilla tracks the user by default," Kuketz writes. "Among other things, information on usage behaviour and crash reports are being shared. You also automatically take part in so-called Firefox studies."

However according to Kuketz, Firefox can "unlike its competitors such as Google Chrome or Microsoft Edge", still be converted into a completely privacy-friendly browser. But you have to look for (or be told about) the setting in order to find it.

For the millions of users who don't often take a look at their privacy settings, Mozilla's decision to force them to actively opt out of tracking means they will also likely continue to unwittingly share data with the company.

To stop sharing data with Mozilla, you'll need to take a deep dive into your privacy settings.

When going into settings, click on Privacy & Security and scroll all the way down until you get to "Firefox data collection and use". Then uncheck all the boxes.

You should also select the setting "blank page" under "Settings/Start page/New windows and tabs/New tabs", as otherwise lots of data is loaded from Mozilla in the background every time you open a new tab.

In addition, you can remove all ticks such as "sponsored shortcuts" under "Firefox Home Content."

And if you don't want to be automatically sharing information with Google, you'll have to change the default search engine under "Settings/Search" and deactivate search suggestions.

Mozilla also occasionally shares data and files with Google in an effort to prevent phishing and other hacking attacks. To turn this off, you need to remove all ticks under "Settings/Privacy & Security/Deceptive Content and Dangerous Software Protection."

 - dpa