What are the steps to reproduce your problem?

1. Inject an execution variable expression-based field into an execution listener
2. Change the variable value by calling expression.setValue("newValue", execution);

What is the problem?

1. The variable is successfully resolved and changed by the called VariableScopeElResolver in the execution here
2. The expression context is not marked as resolved
3. The attempt to set the value ends in an exception with message org.camunda.bpm.engine.impl.javax.el.PropertyNotFoundException: Cannot resolve identifier 'mycolor'

What would be the expected behavior:

1. The expression context is marked as resolved if the variable can be resolved

Hints:
See attached project ZIP support-6456.zip for reproduction