Chrome: Sometimes you don't want spoilers for TV shows or constant photos of your friend's impossibly ugly baby. Maybe you don't want to look at every annoying thing Justin Bieber's up to. Whatever you want to avoid, Rather will replace it with content of your choice.
Rather works in a pretty simple way. You tell it what keywords and phrases you want to avoid by making kill lists. If you don't want to craft your own, popular ones already exist through the service that you can add with a click.
Once you have your kills lined up, you just need to add alternative content sources. Rather accepts Instagram feeds, so you can replace annoying content with photos of pets, food or whatever else.
It's simple, effective and free to use. Just grab it from the Chrome Web Store.