Copying to clipboard in the HTML format when "Reference sequence" is set causes a CRASH

Scenario:

1. Open "COI.aln".
2. Go to the "Highlighting" tab.
3. Set the "Agreements" highlighting value.
4. Go to the "General" tab.
5. Set "Phaneroptera_falcata" as "Reference sequence".
6. Set "Rich text (HTML)" in the "Format" popup menu on th bottom of the "General" tab.
7. Select characters 1-3 of the "Isophya_altaica_EF540820" sequence
8. Click "Copy".
   Expected result: the clipboard contains the data which you can see in the attached file.
   Actual result: CRASH.