Catch errors for occasional readonly properties.
Catch errors for occasional readonly properties.

lyw07/kolibri,mrpau/kolibri,lyw07/kolibri,learningequality/kolibri,indirectlylit/kolibri,mrpau/kolibri,indirectlylit/kolibri,lyw07/kolibri,mrpau/kolibri,lyw07/kolibri,learningequality/kolibri,indirectlylit/kolibri,indirectlylit/kolibri,learningequality/kolibri,learningequality/kolibri,mrpau/kolibri