Is this a bug?
It happens when one changes themes and the themes have different sidebar ids. The widgets used on the previous theme’s sidebar id are not available in the new theme which uses a different sidebar id.
If I change the new theme to use the same sidebar id as the previous theme, in the register_sidebar function, then the previously used widgets show up in the admin panel for widgets but they do not show up on the Web site.
As a user, I would expect the widgets to reset when changing to a new theme and to remember widgets per theme. Or to be able to see in the admin panel all sidebar ids that are holding on to widgets making them unavailable even if they are from themes other than the currently activated theme, and then be able to copy or import the other theme’s sidebar widgets to the new theme’s sidebar.
Currently it has to be done by using the Widget Reset plugin as a workaround or by remembering to remove all widgets from a theme before changing to a new theme which is inconvenient if one wants to change back and forth between themes.
