Fixes Issue #303 (#308)

[skip ci]

Author: rperezlainez

README.md

@@ -751,6 +751,13 @@ val failingMock: Foo = mock[Foo].returnsMT[ErrorOr, MyClass](*) returns Left(Err
 ## Mocking Scala `object`
 
 Since version 1.16.0 it is possible to mock `object` methods, given that such definitions are global, the way to mock them is sligtly different in order to ensure we restore the real implementation of the object after we are done
+
+To enable `withObjectMocked` feature, it is mandatory to create the file `src/test/resources/mockito-extensions/org.mockito.plugins.MockMaker` containing a single line:
+ 
+```scala
+ mock-maker-inline
+```
+
 Example:
 
 ```scala