The sentence you quoted confuses between immutable and final.
I assume by manipulation a change in state or behaviour is intended.
Final when applied to a variable implies that variable reference can't be changed. Remember that final can be applied to a class and variable. When final is applied to a class that class cannot be subclassed.
Immutable is used in conjuction with objects. It is not used in conjuction with variables or classes. Immutable means the object once it is constructed cannot be changed.
Truth is
The object referenced by the final variable can still be manipulated unless the object the variable references is immutable.