mono/monodevelop — comment on commit 580f92041ff943d0dfbdcc3086fc75cbde83983c
File: main/src/core/MonoDevelop.Ide/ExtensionModel/MonoDevelop.Ide.addin.xml line 142
By mhutch:

Type is for custom extension node types, not for the type of the classes that would be plugged in.