Wordpress site not displaying correctly in Firefox
A Wordpress website that I am building is not displaying properly in Firefox (the problem does not occur in Chrome).
As the following video shows, when you clear the cache and then view the site, it displays as intended. However, when you click on the site logo in the top left corner, some elements no longer display full page as they should: https://www.dropbox.com/s/sj05vkhyq5bwxtg/Mark%20Angus%20Firefox%20Video.mov?dl=0
I have been in contact with the theme developers, but I am not sure they have grasped the issue, as they keep coming back to me and saying the site is fine when they view it — but that it is in Chrome which, I have said, is fine. It is with Firefox that the issue occurs.
If anyone could provide me with some advice or suggestions, I would be most grateful.