It's been around as an addon for a while, I think it was put into FF at version 11 (March 2012). I really think it should have remained as an extension, it looks neat but is pretty useless.
Some of the plugins included in contrib, as well as really feature heavy pre-made configs like oh-my-zsh can slow things down. They're good to use as a starting point, but you can make the features you actually want…
It's been around as an addon for a while, I think it was put into FF at version 11 (March 2012). I really think it should have remained as an extension, it looks neat but is pretty useless.
Some of the plugins included in contrib, as well as really feature heavy pre-made configs like oh-my-zsh can slow things down. They're good to use as a starting point, but you can make the features you actually want…