Hi Frank, you probably have discovered how to move tabs between windows. If you can see the tab bars of both windows -- so they need to be resizable windows rather than maximized windows -- you can drag the tabs from one tab bar to the other. Firefox doesn't have a built-in feature to name windows, but it does have a method add-ons can use to add a "preface" to the beginning of the page titles for a window. Here is an examples of that: https://addons.mozilla.org/firefox/addon/window-titler/ If you want a tool that handles both the moving of tabs between windows and naming them, maybe someone has created one. Tabby might cover a lot of it: https://addons.mozilla.org/firefox/addon/tabby-window-tab-manager/