> 'privacy' browser projects based on Chromium for Android

As far as I know none of these projects have tackled the JS fingerprinting problem. The most earnest attempts seem to be Brave and Firefox with the Arkenfox user.js, but they have their own problems. The basic issue is that JS gives websites far too much control over the user's device. The JS spec should have never allowed websites control over the clipboard (e.g. to disable paste), to know if the user is active, when the mouse is being moved, etc. Since it is too late now, short of disabling JS entirely, there will be usability tradeoffs, but I think these are necessary (at least optionally) in an OS like Graphene.

Unfortunately, browsers have often done too little, too late when it comes to privacy. For example, until recently, most browsers allowed third party cookies by default.