You can still develop your own content-blockers without a signing certificate – but there are limitations.
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Apple has just changed the means by which you can develop your own content-blockers.
More details of what a Safari 9 content blocker can use in terms of available triggers and actions.
Unlike iOS 9, it is straightforward to create your own content blockers for El Capitan. Here’s how to do it.
Almost every app that you run – under OS X or iOS – which communicates with a remote web server will use RESTful APIs somewhere along the line.
The Eclectic Light Company 