I had previously deployed application storage in HTML5 to great success in the deployment stage of a few client projects. I used the app cache feature mostly as a way to allow my clients to remotely install kiosk software in their web browser remotely by setting up a temporary "install url" that they would visit and load the app into their browsers. Later, if I needed to patch or update the software, I would simply reestablish that same install url and the app cahce would notice an updated manifest available and reload the application's assets. It worked great.
I just read that Mozilla has announced the app cache features in their browsers are now deprecated and are advocating transition to service workers to duplicate the same functionality. I'm happy to learn the new technology, but was wondering why is this simple, useful and relatively new technology is being canned? And how safe would it be to continue to use it in 2016, judging from the canning of similar web technologies in years past.