In PyQt6, dynamically added widgets sometimes pop out as separate windows due to issues with widget parenting. Every widget in Qt can have an optional parent widget, which dictates its visual placement. Without a parent, or if the parent is lost, a widget becomes a top-level window. This commonly occurs when widgets are created without specifying a parent during initialization. For instance, tabs = QTabWidget() creates a widget without a parent, leading it to float independently. Using tabs = QTabWidget(parent_widget) explicitly assigns a parent, keeping it within the intended container. Reassigning a widget attribute, like self.w = QTabWidget(), can unintentionally replace an existing widget, causing its children to lose their parent and become floating windows. Explicitly setting a widget's parent to None also makes it a standalone window. Even indirect actions, like removing a widget from a layout in certain ways, can clear its parent reference. The solution is to ensure every widget has a parent, either by passing it during creation or by adding it to a layout promptly. The provided example demonstrates dynamic tab creation by consistently setting explicit parents for all widgets. This includes creating new tabs before a designated "+" tab and using blockSignals to prevent recursive signal firing. Understanding and correctly managing widget parenting is crucial for preventing these unexpected floating window behaviors.