The vanilla border baked into the icon texture grew visible again at
large button sizes since the covering rim used a fixed edge thickness.
Both the rim edge and the hotkey's corner inset now scale with the
button size to keep the border hidden and the hotkey clear of the rim
at any size.
Skinning of both the ExtraActionBar and LayerPickerFrame buttons is no longer opt-in. Replaces the old single Skins tab and its toggles with two empty tabs, Extra Action Button and Instance Swap, for future per-frame settings.
Adds the button to ElvUI's anchor/mover system, disables native dragging so it doesn't conflict, filters the now-broken "Reset Position" dropdown entry (scoped to this menu only), and raises the mover overlay above the minimap so it's grabbable in config mode.
Strips the native tooltip-style backdrop pieces off the LayerPickerFrame button and applies the ElvUI backdrop/button style, gated by a new Instance checkbox in the Skins tab.
Narcasung