Per-tab CPU and memory profiling and volume control. Never remove old history items when revisiting a page, but leave the history intact. Treat tabs more like

Per-tab CPU and memory profiling and volume control. Never remove old history items when revisiting a page, but leave the history intact. Treat tabs more like temporary bookmarks (and thus allow bookmark actions to be used with them like search (full-text), (batch) re-naming, arranging in folders, sorting). Notes that can be attached to tabs and to websites. A history of closed tabs. Scripting support with REPL that allows to quickly process content of multiple tabs at once. Transparent access to cookies and localStorage. Something like Privacy Badger included. Place dialog boxes always near the cursor, not in a tiny bar or in a pop-up near the top. Bandwidth stats during page load. Speed: No full-screen transition animations, lazy tab loading, smart tab unloading, ability to quickly and temporarily disable img, embed, video, script etc.