I recently discovered a newer "plugin" for the Firefox and Chrome web browsers called "Disconnect".
https://disconnect.me/
This is an add-on extension to the browsers that filters invisible calls that websites make in the background as you load them. It's easy to add to your browser, and starts protecting you immediately without interference to your normal Internet activities.
There is quite a bit of activity driving tracking, data acquisition and advertising that you normally cannot see. All this takes time as the browser runs Javascript programs in the background, and looks up addresses, then runs more Javascript programs over and over again.
All of this slows down browsing and takes additional connection bandwidth. The statistics being created by Disconnect on my machine show about 9% faster Internet responsiveness and about a 6% savings of bandwidth.
Some of these background activities end up collecting data about what you are doing that gets aggregated and sold. The fact that you like guns is well known in these databases. The aggregated and individual data is then sold commercially. Government is a regular buyer of this information. It is in this way that privacy is being compromised in a big way in today's online world.
Marc
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.