I noticed a minor issue with an icon on a particular area of the Spreadshirt interface.
If you upload a vector design that does not meet all the requirements for vector files, you will see a message “Action Required” below your design in your “Designs” area. After you click that particular design you are prompted with a window that gives you an option to convert to a bitmap or keep as a vector file with corrections made by Spreadshirt.
It is in this window where I am seeing an issue. If you click the “Lighten/Darken Background” icon to make the background dark, the icon does not change to white to maintain visibility. I included two screen captures to clarify what I am speaking of.
Not a big problem, just might cause some frustration with some of your Partners.
EDIT: The browser I was using was Opera, Version:65.0.3467.72


