null pointer exceptions raised when redrawing annotation panel when group annotation 'apply to all' is modified'

I managed to generate the following stack trace on the console:

Null annotation row: ignoring.
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at jalview.gui.AnnotationPanel.drawComponent(AnnotationPanel.java:811)
at jalview.gui.AnnotationPanel.paintComponent(AnnotationPanel.java:673)
at javax.swing.JComponent.paint(Unknown Source)
at javax.swing.JComponent.paintChildren(Unknown Source)
at javax.swing.JComponent.paint(Unknown Source)

Steps to reproduce ? Not verified yet. What I did was :
1. import feredoxin alignemnt.
2. hide several rows and two sets of columns at either end, and one column in middle of view (reconstruct the exploded alignment view for poster)
3. create a new view
4. create group and colour it with hydrophobicity immediately. At this point, the group annotation was on so a new annotation row was created.
5. Unselect 'group consensus'
6, Selected 'apply to all groups'
7.. Selected and then unselected group consensus - the exception was raised then.