What happens when you drag a new transition from the Effects panel on top of an existing transition?

When you drag a new transition from the Effects panel on top of an existing transition, the existing transition is replaced by the new one. This behavior is designed to streamline the editing process, ensuring that only one transition occupies a particular space between clips or in a timeline. By replacing the existing transition, it allows the user to quickly swap out effects without cluttering the timeline with multiple transitions that may not play well together visually or conceptually.

In video editing, managing transitions efficiently is crucial for maintaining a clean and coherent edit. This feature enables editors to experiment with different transitions seamlessly, ensuring the final cut maintains the desired pacing and style. The option to keep both transitions, create a new transition, or combine transitions does not align with how most video editing software handles layering effects.