Random crash reports while clicking on nodes in the supervisor tree view

[OvermindDL1]

Occasionally and seemingly randomly get an occasional error report while clicking on supervisors in the graph view:

=ERROR REPORT==== 5-Apr-2017::14:23:59 ===
** Cowboy handler epl_st_EPL terminating in websocket_handle/3
   for the reason error:badarg
** Message was {text,<<"<6777.435.0>">>}
** Options were []
** Handler state was undefined_state