Mozilla and Commerzbank lead brand retreat from Facebook

It was joined by German financial group Commerzbank, which has similarly brought all advertising to a halt.

Denelle Dixon, Mozilla’s chief business and legal officer, said: “We found that its current default settings leave access open to a lot of data, particularly with respect to settings for third party apps.

“We are encouraged that Mark Zuckerberg has promised to improve the privacy settings and make them more protective. When Facebook takes stronger action in how it shares customer data, specifically strengthening its default privacy settings for third party apps, we’ll consider returning.”

The news comes after Isba publicly called for Facebook to urgently get its house in order, recommending complete transparency of its data sharing safety measures under threat of a full-blown advertiser boycott.

User figures are now also under threat with search variations for 'delete Facebook' increasing 423% since the news broke, according to internet behaviour monitor Hitwise.

Meanwhile, the tech giant's stock has plummeted, with CNN estimating its market value to have dropped by $59bn since the data breach was unveiled.

Facebook has already expressed its ‘outrage’ at its data being misappropriated with Mark Zuckerberg himself acknowledging that Facebook’s first priority of business is to protect its own members.

His business stands accused of allowing user data to fall into the hands of intelligence company Cambridge Analytica, which went on to target users with political messafing.