cannot view structure annotation after dropping pdb structure on sequence

Reported by Roland Dunbrack

0. ensure 'Add secondary structure' and 'Add temperature factor' is enabled in structure preferences
1. import examples/testdata/agc_dmpk_frag.fa
2. drop examples/testdata/AGC_DMPK.pdb onto alignment
3. Right click on the AGC_DMPK sequence - note 'Add reference annotation' option on the Sequence ID submenu is not enabled.

Initial attempts to reproduce this revealed there is a workaround.

Before step 2 above, load AGC_DMPK.pdb as a new alignment (e.g. by dropping it onto the desktop window, rather than the alignment). Then, perform step 2 as before. This time, 'Add reference annotation' is enabled.