When you use the FeatureManager design tree filter, the software waits for you to finish typing before it starts to search. This improves the search behavior for large trees such as assemblies that contain thousands of components.
The improvement applies to the response when you enter characters to increase the specificity of the filter, and if you delete characters to reduce filtering.
When the software begins the search, a progress bar appears, informing you that you can cancel the search by pressing Esc.