A crash to desktop is corrected. Additionally, a merge to LL viewer-development is applied to rule out upstream code correcting the crash.
This crash occurred when a user received an instant message (IM) with the conversations floater closed. A quick flash of the incoming IM notification would occur but, the Chat button inside the toolbar would not flash. When the user pressed the Chat button the viewer would crash.
Updated downloads are available here.
For additional detail see the redmine tracker issue.