The Firefox browser has got a very complete configuration menu with which you can adapt the browser's appearance and behavior to your liking.
But if this settings menu is still too simple for you, try the Configuration Mania extension for Firefox and you'll gain access to a few dozen hidden settings that are not available on the standard Firefox configuration window.
The tweaking options in Configuration Mania are classified into several categories (namely Browser, Security, HTTP network, UI and Defrag) and can be expanded in a convenient tree-like structure from where to access subcategories. The extension is fairly easy to use, but its design could have been improved a bit: the top toolbar features a white space that clearly misses icons, and browsing subcategories often involves a lot of scrolling. Configuration Mania is the perfect Firefox extension for those users who like to be in control of every single detail of their favorite browser.
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