[itsme]

A collection that is defined by a filter or a tab of "Named Filters" is not the best way to implement persistent filters.
It should be possible to apply persistent filters in every scenario where today's filter settings can be applied.
One situation where I frequently miss persistent filters is during editing of a setlist: the right column with songs preselected by filters and a song is missing there because it is not yet added to e.g. the collection that it should be in.

I could imagine extensions like these of the existing filter bar:
- a selection element (window, list box, dropdown...) to choose one out of a list of named persistent filters
- the selected persistent filter settings should be restored into the filter settings on the filter bar to allow further refinement and should be applied to the current selection
- "save" and "save as" for the current filter settings as a persistent filter
Thus persistent filters could be used everywhere where the filter bar is available.
It's an open issue that the filter bar is already rather crowded. That could be solved by allowing to configure available filters or by the possibility to scroll horizontally, both similar to the handling of the tabs on the main library screen.