I am currently working on this website altitudequest.com , I have attached a floating form to the side of the website and adjusted it on the right just that the button to open the form can be seen using the Chrome Dev Tools After uploading the final files to the server one of my user who uses Mozilla told me that the area of the form is affecting the link last link as it was appearing bigger than it was appearing on chrome. So I had to readjust it as per Mozilla which did not solve the problem as it when too much to the right on Chrome

really not able to understand how can this type of design problems can be solved