I was a Firefox fan in the beginning, but I've increasingly found it bloated, both internally and in the UI. Chrome and Opera rain supreme nowadays, but more Chrome. Opera needs to get rid of their useless widget system in favor of extensions. Chrome is very lightweight, and very good at resource management (internal task manager and separate processes). The extensions are extremely easy to build as well, and can range from a simple search bar to a complex music player
. In this day and age, all you really need is a lightweight browser with an Adblocker. Everything extra is per your preference. Unfortunately adblockers will never be included in the big browsers by default since too much is made from advertisements and there would be a ton of lawsuits.