Each Firefox release there are some updates made to match the changing RFC standards and up to date with web design performance. However the developer of the website will be the one to support and keep track of these changes. I ight suggest to contact the site owner or to open up a ticket in the webcompat.com site. 

Hi tarboat, I understand that the site will no longer display as expected. Please first try these steps: [[Websites look wrong or appear differently than they should]] as well as Safe Mode to see if its an add on compatibility issue: [[Troubleshoot Firefox issues using Safe Mode]] Each Firefox release there are some updates made to match the changing RFC standards and up to date with web design performance. However the developer of the website will be the one to support and keep track of these changes. I ight suggest to contact the site owner or to open up a ticket in the webcompat.com site. For more help in the developer community, I would encourage checking out stackoverflow.com as well.