Parsing error on exporting annotation to the GTF format

Affected test:
GUITest_common_scenarios_annotations_test_0011_3.

Scenario:

1. Open "samples/FASTA/human_T1.fa"
2. Create an annotation, set e.g. "ann" annotation name and "200..300" region.
3. Add "gene_id" and "transcript_id" qualifiers.
4. Export the annotation to the GTF format. Make sure the "Add to project" option is checked in the export dialog.
   Expected state: The export has finished without errors. The document has been added to the project.
   Actual state:

   [TRACE][11:11] GTF parsing error: unexpected value of the "feature" value "ann" at line 1!
   [ERROR][11:11] GTF parsing error: one or more errors occurred while 
   parsing the input file, see TRACE log for details!
   

If the "Add to project" option is not checked, the export works fine.