The window dragged at ~185 ms a step. Two causes, both in the shell: the waveform strip read the guest's audio buffer sixty times a second through a synchronous webview call that stalled on the busy main process, and macOS waits on the piece guest's compositor frame for every step of a resize while the AC runtime keeps it painting at 60 fps. The strip now reads the host's own mute state, backs off to eight reads a second in silence, and pauses during a drag; the guest is swapped for a snapshot of its last frame for the drag and thawed on settle; the notebook ruling, layout, prompt and donkey wait for the settle too. A step is now ~30 ms, under a plain Chrome window. The provider dropdown could not be switched by mouse: opening it focused the current option, a press on another blurred it, and the focus-out handler closed the list before the click landed. Provider and Model now share one dropdown of the same weight, the model rows name the family and version with the alias beside them, the status line says which model is running, and the AC row wears a looping pal from pals.aesthetic.computer. Menu bar reads Aesel from the bundle name; window titles stay aesel. The aesel page shows the real Studio window and lists Mac now, iPhone next. Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>