Workflow window with breakpoint does not closed after 100% execution

Scenario:

1. Open Preferences.
2. The "Application Settings" dialog appears.
3. Open the "Workflow Designer" tab.
4. Check "Enable debugger".
5. Click OK.
6. Open ".../data/workflow_samples/Scenarios/find_sequences.uwl".
7. A workflow window appears.
8. Select "Read Sequence"
9. Set ".../samples/Fasta/" and ../data/samples.GenBank/sars.gb as input.
10. Select "Find Pattern" and set patten "acgt"
11. Select the "Write Sequence" element and click "Break at element" on the toolbar.
12. Run workflow.
13. Close the workflow window. Don't wait for the workflow to finish and don't save your changes.
    Expected state: The workflow finished successfully, no any tasks in the Task window
    Current state: Task is not finished while all tasks show 100% execution, see attachment
14. Close Ugene twice
    MESSAGEBOX_TEXT: Shutdown already in process. Close UGENE immediately?
    Only after these actions UGENE is closed