Hello urmas,
There are known issues using Firefox 41 or later due to an internal code change in Mozilla browser. You might see many other similar issues as this is not exclusive to the page that you are mentioning.
This has been documented in the following KB Article:
http://www.ca.com/us/support/ca-support-online/product-content/knowledgebase-articles/tec1040434.aspx
This has been fixed in 14.3 patch 1 and later releases.
I would recommend that you use a different supported browser and that you plan for a PPM upgrade to the latest available release; this is because FF 40 or earlier are not supported by Mozilla anymore and do not include the latest security patches. As a reminder, Clarity PPM 13.3 will be out of support on October 30 as well.
Thanks,
Marc