How to reproduce

• Insert a content digest service.
• In the parameter box, select a content type that has some custom views and check that all the views are displayed in the combo.
• Add another content type to the selection, which does not have the custom views. The view list should have only the default views.
• Deselect the second content type, leaving only the first selected. The custom views aren't displayed anymore.

Even after refreshing the page, the custom views are still absent. The only solution is to restart the server.