Extras Bridge is a Scripts software developed by Unknown Publisher. After our trial and test, the software is proved to be official, secure and free. Here is the official description for Extras Bridge:

Edit by Marydown: This is helpful whenever a developer cannot export function from his DLLs, he's struggling with unloading .NET plugins from Skype's process space or he wants his .NET plugin to be hosted by the Skype Plugin MANAGER.The Extras Bridge dynamically linked Library is registered with Skype as a Type-B plugin.To fully support runtime load/unload feature, it spawns a child process Extras Host. Together they will act as lightweight Mediator between Skype and your plugin implementation. The host process inspects all the dll assemblies, from within its own directory, looking for first non-Abstract public class implementing IPluginFactory.When found, it is going to use it to instantiate your ISkypePluginB implementation.