vSphere 5.5 web console works on windows but not mac

I'm having trouble getting the web console to work on Mac/Firefox 28. If I login on a Windows 7 PC with Firefox it works just fine.

On the Win7 pc the launched url looks like this

https://vc.domain.com:9443/vsphere-client/vmrc/vmrc.jsp?vm=urn:vmomi:VirtualMachine:vm-70:BE0A6B28-CA11-4676-8451-14BF88FF4DE3

On mac the launched URL looks like this

http://vc.domain.com:7331/console/?vmId=vm-70&vmName=Dev&host=vc.domain.com&sessionTicket=cst-VCT-52fa4df0-72e7-c733-4bad-3c96e66b38ef--tp-74-F9-48-F0-08-2C-D9-A3-0C-5E-BC-E4-34-03-23-59-F6-25-AF-9C&thumbprint=74:F9:48:F0:08:2C:D9:A3:0C:5E:BC:E4:34:03:23:59:F6:25:AF:9C

I've reinstalled the integration plugin on the mac a few times, but nothing is changing. Any ideas why I'm seeing this different behavior?