New: Everything. JSB 5 is a complete rewrite of JSB. It's faster in every way. It's easier and more efficient to use. The UI is cleaner. It comes in colors. It's safer. But it's nowhere near done. Don't expect everything to work flawlessy. Some features might not exist yet. Some settings have no effect. The settings UI is not finalized. You can't edit or delete rules you've created. You can, however, import rules from JSB 4. Most features and more are available to test. User scripts can be installed when visiting a page ending in ".user.js", but you cannot modify or remove it once added. Full rule management is not yet available, but you can still create rules from the page editor. The Windows version of Safari is no longer supported (unless Apple ever decides to update it.)