Mozilla plans to collect browsing data from Firefox users in a "privacy preserving way" to help Firefox product teams improve the browser based on the data.
Mozilla's Georg Fritzsche published information on the plan to collect additional data yesterday on the Mozilla Governance group.
In it, he describes the issue that Mozilla engineers face currently. While Firefox may collect the data when users opt-in, Mozilla believes that the data is biased and that only data collecting with opt-out would provide unbiased data that the engineers can work with.
Questions that this data may help answer include "which top sites are users visiting", "which sites using Flash does a user encounter", and "which sites does a user see heavy Jank on" according to Fritzsche.
The solution that Fritzsche proposes uses differential privacy and the open source RAPPOR project by Google.
The key idea behind differential privacy is that any query against a set of data should not reveal whether a specific person or that person's data is present. This is done by introducing randomness to the data.
Mozilla plans to run a study on a subset of Firefox's release population to test the implementation. The organization plans to make this opt-out, which means that Firefox users need to disable this actively if they don't want their browsing data -- in anonymized form -- submitted to Mozilla.
What we plan to do now is run an opt-out SHIELD study  to validate our implementation of RAPPOR. This study will collect the value for users’ home page (eTLD+1) for a randomly selected group of our release population We are hoping to launch this in mid-September.
This is not the type of data we have collected as opt-out in the past and is a new approach for Mozilla. As such, we are still experimenting with the project and wanted to reach out for feedback.
The telemetry that Mozilla plans to collect will only collect the top level domain name, e.g. ghacks.net without subdomains or directories.
Google and Apple use differential privacy already, Google does in Chrome for instance.
Mozilla has yet to reveal how users may opt-out of the study. We will update the article as soon as this is revealed by the company.
One objection that Firefox users had who replied to the post on Google Groups or elsewhere was that making the feature opt-out was anti-privacy no matter if the data that is collected cannot be traced back to a single user.
Others stated that Mozilla could some of the data otherwise, for instance by crawling sites to check if they still make use of Flash, or by using services to retrieve information on the top sites on the Web.
Now You: What's your take on the proposal?