remove undeifned properties before sending postMessage 
remove undeifned properties before sending postMessage 

-- avoids JSON parsing errors with undefined properties 
vladm3/mwEmbed,matsuu/mwEmbed,alexmilk/mwEmbed,panda-os/mwEmbed,omridevk/mwEmbed,matsuu/mwEmbed,joanpuigsanz/mwEmbed,DBezemer/mwEmbed,kaltura/mwEmbed,omridevk/mwEmbed,safarijv/mwEmbed,tanyaLibatter/mwEmbed,bordar/mwEmbed,bordar/mwEmbed,SVSG/mwEmbed,SVSG/mwEmbed,panda-os/mwEmbed,FlixMaster/mwEmbed,SVSG/mwEmbed,DBezemer/mwEmbed,alexmilk/mwEmbed,DBezemer/mwEmbed,FlixMaster/mwEmbed,joanpuigsanz/mwEmbed,slash851/mwEmbed,bordar/mwEmbed,safarijv/mwEmbed,omridevk/mwEmbed,matsuu/mwEmbed,kaltura/mwEmbed,kaltura/mwEmbed,slash851/mwEmbed,slash851/mwEmbed,abaylis/mwEmbed,FlixMaster/mwEmbed,alexmilk/mwEmbed,vladm3/mwEmbed,abaylis/mwEmbed,joanpuigsanz/mwEmbed,panda-os/mwEmbed,tanyaLibatter/mwEmbed,abaylis/mwEmbed,alexmilk/mwEmbed,matsuu/mwEmbed,abaylis/mwEmbed,vladm3/mwEmbed,safarijv/mwEmbed,FlixMaster/mwEmbed,safarijv/mwEmbed,kaltura/mwEmbed,DBezemer/mwEmbed,omridevk/mwEmbed,vladm3/mwEmbed,bordar/mwEmbed,SVSG/mwEmbed,tanyaLibatter/mwEmbed,tanyaLibatter/mwEmbed,panda-os/mwEmbed,slash851/mwEmbed,joanpuigsanz/mwEmbed