Using widgets removes hard coded theme (plugin) sidebar objects

Hi All

So far, I have been manually entering code from plugins to the “sidebar.php” file of my current theme (silveray). Anyway, since I am just testing things, I decided try using a widget and dragged it to the right sidebar. This action displayed the widget in the sidebar as expected but it also caused the other objects (blocks/modules for example Meta, Categories, Pages, etc) or whatever they are called in WordPress to disappear. It appears that widgets cannot be used with hard-coded theme sidebar items.

Is this normal in WordPress? How can this be addressed? Is there a way to have both widgets and hard-coded sidebar objects.