Bug description

Trying to save a non-installed method in the debugger cause an exception

To Reproduce

1. execute

nil executeMethod: (Smalltalk compiler compile: 'foo ^ self doesNotExists').

2. get a debug window #doesNotExists was sent to nil
3. edit the code (remove doesNotExists for instance)
4. save (ctrl-s)
5. get a second debug window KeyNotFound: key #foo not found in MethodDictionary

Expected behavior

If possible, replace the method in the stack without installing the method.
Alternatively, get an error message like the one we DoIt methods.

Version information:

• Pharo Version 11