qml: minor optimization
- Set root type
Item
rather thanRectangle
. See docs:
Applications with a monochrome background should set it using QQuickWindow::setColor() rather than using a top-level Rectangle item. QQuickWindow::setColor() will be used in a call to glClear(), which is potentially faster.
- Constraint miniplayer background effect source to
stackView
, so that updates on the playlist or other irrelevant areas do not cause the effect to be updated (It is assumed playlist is never part of miniplayer background).