Firefox itself isn't. But configuring the UI and getting some functionality in is. (Some) extensions are huge bundles of functionality, affecting things all ove

Firefox itself isn't. But configuring the UI and getting some functionality in is. (Some) extensions are huge bundles of functionality, affecting things all over the place. It's not a fault of firefox, but firefox caused it by not having very basic functionality built in (namely tab ordering, cycling, ...). Then there are frustrating things like how do I move the reload/stop button to the left? Why do have quite powerful UI customization when it doesn't allow such a simple operation?