In order to reduce file size I have removed support for IE6-9. I was wondering how you could automatically set a fallback/backup image (JPG/GIF) to display when an older or unsupported browser is detected?
My understanding is it is not required for Double-click as you upload the fallback image separately (?), however, some providers seem to require this to be done at the banner level and I can’t seem to find anyway to go about it here.
Would very much appreciate any assistance.