Hello, Seems there is some difference between Firefox and other browsers. If you want to overwritethe src of an image, you can use "content" from css. In my case this is used for customerspecific styling, being done via CSS only, while the default image is provided directly over src attribute inside html. https://jsfiddle.net/atXoR/qn4he25v/ This Problem appears in '''Firefox for Windows''' and '''Firefox for Android''' This Problem doesnt appear for Chromium', Firefox on IOs, Safari on IOs Greetings, Stephan